diff --git a/scenes/marketplace_ui.tscn b/scenes/marketplace_ui.tscn
new file mode 100644
index 0000000..ca5bb6a
--- /dev/null
+++ b/scenes/marketplace_ui.tscn
@@ -0,0 +1,96 @@
+[gd_scene load_steps=2 format=3]
+
+[ext_resource type="Script" path="res://scripts/marketplace_ui.gd" id="1_mpu"]
+
+[node name="MarketplaceUI" type="Control"]
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+script = ExtResource("1_mpu")
+
+[node name="VBox" type="VBoxContainer" parent="."]
+layout_mode = 1
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+offset_left = 32.0
+offset_top = 32.0
+offset_right = -32.0
+offset_bottom = -32.0
+grow_horizontal = 2
+grow_vertical = 2
+theme_override_constants/separation = 12
+
+[node name="HeaderHBox" type="HBoxContainer" parent="VBox"]
+layout_mode = 2
+theme_override_constants/separation = 16
+
+[node name="BackButton" type="Button" parent="VBox/HeaderHBox"]
+custom_minimum_size = Vector2(100, 36)
+layout_mode = 2
+text = "< Back"
+
+[node name="TitleLabel" type="Label" parent="VBox/HeaderHBox"]
+layout_mode = 2
+size_flags_horizontal = 3
+theme_override_font_sizes/font_size = 24
+text = "Marketplace"
+horizontal_alignment = 1
+
+[node name="BalanceLabel" type="Label" parent="VBox/HeaderHBox"]
+layout_mode = 2
+theme_override_font_sizes/font_size = 18
+theme_override_colors/font_color = Color(1, 0.84, 0, 1)
+text = "Wallet: 0 CR"
+
+[node name="RefreshButton" type="Button" parent="VBox/HeaderHBox"]
+custom_minimum_size = Vector2(100, 36)
+layout_mode = 2
+text = "Refresh"
+
+[node name="FilterBar" type="HBoxContainer" parent="VBox"]
+layout_mode = 2
+theme_override_constants/separation = 8
+
+[node name="SearchEdit" type="LineEdit" parent="VBox/FilterBar"]
+custom_minimum_size = Vector2(200, 36)
+layout_mode = 2
+size_flags_horizontal = 3
+placeholder_text = "Search items by name or description..."
+
+[node name="TypeOption" type="OptionButton" parent="VBox/FilterBar"]
+custom_minimum_size = Vector2(140, 36)
+layout_mode = 2
+
+[node name="MinPriceEdit" type="LineEdit" parent="VBox/FilterBar"]
+custom_minimum_size = Vector2(90, 36)
+layout_mode = 2
+placeholder_text = "Min CR"
+
+[node name="MaxPriceEdit" type="LineEdit" parent="VBox/FilterBar"]
+custom_minimum_size = Vector2(90, 36)
+layout_mode = 2
+placeholder_text = "Max CR"
+
+[node name="SearchBtn" type="Button" parent="VBox/FilterBar"]
+custom_minimum_size = Vector2(90, 36)
+layout_mode = 2
+text = "Search"
+
+[node name="StatusLabel" type="Label" parent="VBox"]
+layout_mode = 2
+horizontal_alignment = 1
+
+[node name="Scroll" type="ScrollContainer" parent="VBox"]
+layout_mode = 2
+size_flags_vertical = 3
+
+[node name="ListingsGrid" type="GridContainer" parent="VBox/Scroll"]
+layout_mode = 2
+size_flags_horizontal = 3
+theme_override_constants/h_separation = 16
+theme_override_constants/v_separation = 16
+columns = 4
diff --git a/scripts/marketplace_ui.gd b/scripts/marketplace_ui.gd
new file mode 100644
index 0000000..a3d8f66
--- /dev/null
+++ b/scripts/marketplace_ui.gd
@@ -0,0 +1,231 @@
+extends Control
+class_name MarketplaceUI
+## Marketplace Browse & Buy UI panel.
+##
+## Displays:
+## - Search bar with keyword, item type, and price filters
+## - Marketplace active listings cards
+## - Item details and direct atomic purchase flow
+## - Wallet balance and real-time status feedback
+##
+## docs/planning/economy.md US-6 (task 9797a0cfd9e6).
+
+signal back_requested
+signal item_purchased(listing_id: int)
+
+@onready var back_button: Button = $VBox/HeaderHBox/BackButton
+@onready var refresh_button: Button = $VBox/HeaderHBox/RefreshButton
+@onready var balance_label: Label = $VBox/HeaderHBox/BalanceLabel
+@onready var status_label: Label = $VBox/StatusLabel
+
+# Filter inputs
+@onready var search_edit: LineEdit = $VBox/FilterBar/SearchEdit
+@onready var type_option: OptionButton = $VBox/FilterBar/TypeOption
+@onready var min_price_edit: LineEdit = $VBox/FilterBar/MinPriceEdit
+@onready var max_price_edit: LineEdit = $VBox/FilterBar/MaxPriceEdit
+@onready var search_btn: Button = $VBox/FilterBar/SearchBtn
+
+# Listings container
+@onready var listings_container: GridContainer = $VBox/Scroll/ListingsGrid
+
+var _api_client: Node = null
+
+
+func _ready() -> void:
+	_api_client = _get_api()
+	_setup_type_options()
+	_wire_signals()
+	if _api_client != null and _api_client.has_token():
+		refresh_balance()
+		search_listings()
+
+
+func _get_api() -> Node:
+	if has_node("/root/ApiClient"):
+		return get_node("/root/ApiClient")
+	return null
+
+
+func _setup_type_options() -> void:
+	if not type_option:
+		return
+	type_option.clear()
+	type_option.add_item("All Types", 0)
+	type_option.add_item("Avatar Item", 1)
+	type_option.add_item("Asset", 2)
+	type_option.add_item("Experience Pass", 3)
+
+
+func _wire_signals() -> void:
+	if back_button and not back_button.pressed.is_connected(_on_back_pressed):
+		back_button.pressed.connect(_on_back_pressed)
+	if refresh_button and not refresh_button.pressed.is_connected(refresh_all):
+		refresh_button.pressed.connect(refresh_all)
+	if search_btn and not search_btn.pressed.is_connected(search_listings):
+		search_btn.pressed.connect(search_listings)
+	if search_edit and not search_edit.text_submitted.is_connected(func(_txt): search_listings()):
+		search_edit.text_submitted.connect(func(_txt): search_listings())
+
+
+func _on_back_pressed() -> void:
+	back_requested.emit()
+
+
+func show_status(text: String, is_error: bool = false) -> void:
+	if not status_label:
+		return
+	status_label.text = text
+	if is_error:
+		status_label.add_theme_color_override("font_color", Color(1.0, 0.3, 0.3))
+	else:
+		status_label.add_theme_color_override("font_color", Color(0.3, 0.9, 0.3))
+
+
+func refresh_all() -> void:
+	refresh_balance()
+	search_listings()
+
+
+func refresh_balance() -> void:
+	var api = _get_api()
+	if not api or not api.has_token():
+		return
+	var res: Dictionary = await EconomyApiClient.get_wallet(api)
+	if res.ok and res.data is Dictionary:
+		var balance: int = int(res.data.get("balance", 0))
+		if balance_label:
+			balance_label.text = "Wallet: %d CR" % balance
+
+
+func search_listings() -> void:
+	var api = _get_api()
+	if not api:
+		return
+
+	var q: String = search_edit.text.strip_edges() if search_edit else ""
+	var item_type: String = ""
+	if type_option and type_option.selected > 0:
+		match type_option.selected:
+			1: item_type = "avatar_item"
+			2: item_type = "asset"
+			3: item_type = "experience_pass"
+
+	var min_price: int = -1
+	if min_price_edit and min_price_edit.text.is_valid_int():
+		min_price = min_price_edit.text.to_int()
+
+	var max_price: int = -1
+	if max_price_edit and max_price_edit.text.is_valid_int():
+		max_price = max_price_edit.text.to_int()
+
+	show_status("Loading listings...")
+	var res: Dictionary = await EconomyApiClient.search_listings(api, q, item_type, min_price, max_price)
+	if res.ok and res.data is Dictionary:
+		var items: Array = res.data.get("listings", [])
+		render_listings(items)
+		show_status("Found %d active listings" % items.size())
+	else:
+		show_status("Search failed: " + res.detail, true)
+
+
+func render_listings(listings: Array) -> void:
+	if not listings_container:
+		return
+
+	for c in listings_container.get_children():
+		listings_container.remove_child(c)
+		c.queue_free()
+
+	if listings.is_empty():
+		var empty_lbl := Label.new()
+		empty_lbl.text = "No listings matching your search."
+		empty_lbl.add_theme_color_override("font_color", Color(0.6, 0.6, 0.6))
+		listings_container.add_child(empty_lbl)
+		return
+
+	for l in listings:
+		if not l is Dictionary:
+			continue
+		var card := _create_listing_card(l)
+		listings_container.add_child(card)
+
+
+func _create_listing_card(listing: Dictionary) -> Control:
+	var card := PanelContainer.new()
+	card.custom_minimum_size = Vector2(240, 200)
+
+	var margin := MarginContainer.new()
+	margin.add_theme_constant_override("margin_left", 12)
+	margin.add_theme_constant_override("margin_top", 12)
+	margin.add_theme_constant_override("margin_right", 12)
+	margin.add_theme_constant_override("margin_bottom", 12)
+	card.add_child(margin)
+
+	var vbox := VBoxContainer.new()
+	vbox.add_theme_constant_override("separation", 8)
+	margin.add_child(vbox)
+
+	var cat_item: Dictionary = listing.get("catalog_item", {})
+	var title_lbl := Label.new()
+	title_lbl.text = str(cat_item.get("name", "Unnamed Item"))
+	title_lbl.add_theme_font_size_override("font_size", 16)
+	vbox.add_child(title_lbl)
+
+	var type_lbl := Label.new()
+	var itype: String = str(cat_item.get("item_type", "")).replace("_", " ").capitalize()
+	type_lbl.text = itype
+	type_lbl.add_theme_color_override("font_color", Color(0.4, 0.7, 1.0))
+	type_lbl.add_theme_font_size_override("font_size", 12)
+	vbox.add_child(type_lbl)
+
+	var seller_lbl := Label.new()
+	var seller_name: String = str(listing.get("seller_username", "Unknown"))
+	seller_lbl.text = "By " + seller_name
+	seller_lbl.add_theme_color_override("font_color", Color(0.6, 0.6, 0.6))
+	seller_lbl.add_theme_font_size_override("font_size", 12)
+	vbox.add_child(seller_lbl)
+
+	var desc_lbl := Label.new()
+	var desc: String = str(cat_item.get("description", ""))
+	if desc.length() > 60:
+		desc = desc.substr(0, 57) + "..."
+	desc_lbl.text = desc
+	desc_lbl.size_flags_vertical = Control.SIZE_EXPAND_FILL
+	desc_lbl.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
+	vbox.add_child(desc_lbl)
+
+	var bottom_hbox := HBoxContainer.new()
+	vbox.add_child(bottom_hbox)
+
+	var price: int = int(listing.get("price", 0))
+	var price_lbl := Label.new()
+	price_lbl.text = "%d CR" % price
+	price_lbl.add_theme_font_size_override("font_size", 16)
+	price_lbl.add_theme_color_override("font_color", Color(1.0, 0.8, 0.2))
+	price_lbl.size_flags_horizontal = Control.SIZE_EXPAND_FILL
+	bottom_hbox.add_child(price_lbl)
+
+	var buy_btn := Button.new()
+	buy_btn.text = "Buy"
+	buy_btn.custom_minimum_size = Vector2(80, 32)
+	var listing_id: int = int(listing.get("id", 0))
+	buy_btn.pressed.connect(_on_buy_clicked.bind(listing_id, str(cat_item.get("name", "Item")), price))
+	bottom_hbox.add_child(buy_btn)
+
+	return card
+
+
+func _on_buy_clicked(listing_id: int, item_name: String, price: int) -> void:
+	var api = _get_api()
+	if not api or not api.has_token():
+		show_status("Please login to purchase items", true)
+		return
+
+	show_status("Purchasing '%s' for %d CR..." % [item_name, price])
+	var res: Dictionary = await EconomyApiClient.purchase_listing(api, listing_id)
+	if res.ok:
+		show_status("Successfully purchased '%s'! Item added to inventory." % item_name)
+		item_purchased.emit(listing_id)
+		refresh_all()
+	else:
+		show_status("Purchase failed: " + res.detail, true)
diff --git a/scripts/smoke_test_marketplace_ui.gd b/scripts/smoke_test_marketplace_ui.gd
new file mode 100644
index 0000000..c1564cd
--- /dev/null
+++ b/scripts/smoke_test_marketplace_ui.gd
@@ -0,0 +1,72 @@
+extends SceneTree
+## Headless smoke test for MarketplaceUI scene and script.
+
+func _initialize() -> void:
+	_run()
+
+func _run() -> void:
+	await process_frame
+	print("[SMOKE] Starting MarketplaceUI smoke test...")
+
+	var scene = load("res://scenes/marketplace_ui.tscn")
+	if not scene:
+		printerr("[FAIL] Could not load scenes/marketplace_ui.tscn")
+		quit(1)
+		return
+
+	var ui: Control = scene.instantiate()
+	root.add_child(ui)
+	await process_frame
+
+	# Verify onready nodes
+	assert(ui.back_button != null, "Missing back_button")
+	assert(ui.refresh_button != null, "Missing refresh_button")
+	assert(ui.balance_label != null, "Missing balance_label")
+	assert(ui.status_label != null, "Missing status_label")
+	assert(ui.search_edit != null, "Missing search_edit")
+	assert(ui.type_option != null, "Missing type_option")
+	assert(ui.min_price_edit != null, "Missing min_price_edit")
+	assert(ui.max_price_edit != null, "Missing max_price_edit")
+	assert(ui.search_btn != null, "Missing search_btn")
+	assert(ui.listings_container != null, "Missing listings_container")
+
+	# Verify type options populated
+	assert(ui.type_option.item_count >= 4, "Type options not populated")
+
+	# Test rendering empty listings
+	ui.render_listings([])
+	assert(ui.listings_container.get_child_count() == 1, "Should show empty notice")
+
+	# Test rendering sample listings
+	var sample_listings = [
+		{
+			"id": 10,
+			"price": 200,
+			"seller_username": "merchant_bob",
+			"catalog_item": {
+				"name": "Wizard Robe",
+				"item_type": "avatar_item",
+				"description": "Flowing velvet robe"
+			}
+		},
+		{
+			"id": 11,
+			"price": 500,
+			"seller_username": "dungeon_master",
+			"catalog_item": {
+				"name": "Castle Map",
+				"item_type": "asset",
+				"description": "Detailed 3D fortress map"
+			}
+		}
+	]
+	ui.render_listings(sample_listings)
+	assert(ui.listings_container.get_child_count() == 2, "Should render 2 listing cards")
+
+	# Verify signals
+	assert(ui.has_signal("back_requested"), "Missing back_requested signal")
+	assert(ui.has_signal("item_purchased"), "Missing item_purchased signal")
+
+	ui.queue_free()
+	print("[SMOKE] MarketplaceUI smoke test PASSED")
+	quit(0)