diff --git a/src/components/atoms/ComponentTreeNode.tsx b/src/components/atoms/ComponentTreeNode.tsx
index 186bede..8b42047 100644
--- a/src/components/atoms/ComponentTreeNode.tsx
+++ b/src/components/atoms/ComponentTreeNode.tsx
@@ -17,6 +17,9 @@ interface ComponentTreeNodeProps {
   onDragLeave: (e: React.DragEvent) => void
   onDrop: (e: React.DragEvent) => void
   depth?: number
+  hasChildren?: boolean
+  isExpanded?: boolean
+  onToggleExpand?: () => void
 }
 
 export function ComponentTreeNode({
@@ -33,10 +36,12 @@ export function ComponentTreeNode({
   onDragLeave,
   onDrop,
   depth = 0,
+  hasChildren = false,
+  isExpanded = false,
+  onToggleExpand,
 }: ComponentTreeNodeProps) {
   const def = getComponentDef(component.type)
   const IconComponent = def ? (Icons as any)[def.icon] || Icons.Cube : Icons.Cube
-  const hasChildren = Array.isArray(component.children) && component.children.length > 0
   
   return (
     <div className="relative">
@@ -67,7 +72,19 @@ export function ComponentTreeNode({
         )}
       >
         {hasChildren ? (
-          <Icons.CaretDown className="w-3 h-3 text-muted-foreground" />
+          <button
+            onClick={(e) => {
+              e.stopPropagation()
+              onToggleExpand?.()
+            }}
+            className="hover:text-accent"
+          >
+            {isExpanded ? (
+              <Icons.CaretDown className="w-3 h-3 text-muted-foreground" />
+            ) : (
+              <Icons.CaretRight className="w-3 h-3 text-muted-foreground" />
+            )}
+          </button>
         ) : (
           <div className="w-3" />
         )}
diff --git a/src/components/molecules/ComponentTree.tsx b/src/components/molecules/ComponentTree.tsx
index 72cd9e6..6290fd4 100644
--- a/src/components/molecules/ComponentTree.tsx
+++ b/src/components/molecules/ComponentTree.tsx
@@ -1,9 +1,10 @@
+import { useState, useCallback } from 'react'
 import { UIComponent } from '@/types/json-ui'
 import { ComponentTreeNode } from '@/components/atoms/ComponentTreeNode'
 import { PanelHeader } from '@/components/atoms'
 import { ScrollArea } from '@/components/ui/scroll-area'
 import { Button } from '@/components/ui/button'
-import { Tree, Plus } from '@phosphor-icons/react'
+import { Tree, CaretDown, CaretRight } from '@phosphor-icons/react'
 
 interface ComponentTreeProps {
   components: UIComponent[]
@@ -34,39 +35,108 @@ export function ComponentTree({
   onDragLeave,
   onDrop,
 }: ComponentTreeProps) {
+  const [expandedIds, setExpandedIds] = useState<Set<string>>(new Set())
+
+  const getAllComponentIds = useCallback((comps: UIComponent[]): string[] => {
+    const ids: string[] = []
+    const traverse = (components: UIComponent[]) => {
+      components.forEach((comp) => {
+        if (Array.isArray(comp.children) && comp.children.length > 0) {
+          ids.push(comp.id)
+          traverse(comp.children)
+        }
+      })
+    }
+    traverse(comps)
+    return ids
+  }, [])
+
+  const handleExpandAll = useCallback(() => {
+    const allIds = getAllComponentIds(components)
+    setExpandedIds(new Set(allIds))
+  }, [components, getAllComponentIds])
+
+  const handleCollapseAll = useCallback(() => {
+    setExpandedIds(new Set())
+  }, [])
+
+  const toggleExpand = useCallback((id: string) => {
+    setExpandedIds((prev) => {
+      const next = new Set(prev)
+      if (next.has(id)) {
+        next.delete(id)
+      } else {
+        next.add(id)
+      }
+      return next
+    })
+  }, [])
+
   const renderTree = (comps: UIComponent[], depth = 0) => {
-    return comps.map((comp) => (
-      <div key={comp.id}>
-        <ComponentTreeNode
-          component={comp}
-          isSelected={selectedId === comp.id}
-          isHovered={hoveredId === comp.id}
-          isDraggedOver={draggedOverId === comp.id}
-          dropPosition={draggedOverId === comp.id ? dropPosition : null}
-          onSelect={() => onSelect(comp.id)}
-          onHover={() => onHover(comp.id)}
-          onHoverEnd={onHoverEnd}
-          onDragStart={(e) => onDragStart(comp.id, e)}
-          onDragOver={(e) => onDragOver(comp.id, e)}
-          onDragLeave={onDragLeave}
-          onDrop={(e) => onDrop(comp.id, e)}
-          depth={depth}
-        />
-        {Array.isArray(comp.children) && comp.children.length > 0 && (
-          <div>{renderTree(comp.children, depth + 1)}</div>
-        )}
-      </div>
-    ))
+    return comps.map((comp) => {
+      const hasChildren = Array.isArray(comp.children) && comp.children.length > 0
+      const isExpanded = expandedIds.has(comp.id)
+
+      return (
+        <div key={comp.id}>
+          <ComponentTreeNode
+            component={comp}
+            isSelected={selectedId === comp.id}
+            isHovered={hoveredId === comp.id}
+            isDraggedOver={draggedOverId === comp.id}
+            dropPosition={draggedOverId === comp.id ? dropPosition : null}
+            onSelect={() => onSelect(comp.id)}
+            onHover={() => onHover(comp.id)}
+            onHoverEnd={onHoverEnd}
+            onDragStart={(e) => onDragStart(comp.id, e)}
+            onDragOver={(e) => onDragOver(comp.id, e)}
+            onDragLeave={onDragLeave}
+            onDrop={(e) => onDrop(comp.id, e)}
+            depth={depth}
+            hasChildren={hasChildren}
+            isExpanded={isExpanded}
+            onToggleExpand={() => toggleExpand(comp.id)}
+          />
+          {hasChildren && isExpanded && comp.children && (
+            <div>{renderTree(comp.children, depth + 1)}</div>
+          )}
+        </div>
+      )
+    })
   }
 
   return (
     <div className="h-full flex flex-col">
       <div className="p-4">
-        <PanelHeader
-          title="Component Tree"
-          subtitle={`${components.length} component${components.length !== 1 ? 's' : ''}`}
-          icon={<Tree size={20} weight="duotone" />}
-        />
+        <div className="flex items-center justify-between mb-2">
+          <PanelHeader
+            title="Component Tree"
+            subtitle={`${components.length} component${components.length !== 1 ? 's' : ''}`}
+            icon={<Tree size={20} weight="duotone" />}
+          />
+          {components.length > 0 && (
+            <div className="flex gap-1">
+              <Button
+                variant="ghost"
+                size="sm"
+                onClick={handleExpandAll}
+                className="h-7 w-7 p-0"
+                title="Expand All"
+              >
+                <CaretDown size={16} />
+              </Button>
+              <Button
+                variant="ghost"
+                size="sm"
+                onClick={handleCollapseAll}
+                className="h-7 w-7 p-0"
+                title="Collapse All"
+              >
+                <CaretRight size={16} />
+              </Button>
+            </div>
+          )}
+        </div>
       </div>
       
       <ScrollArea className="flex-1">