diff --git a/browser_tests/fixtures/ComfyPage.ts b/browser_tests/fixtures/ComfyPage.ts
index 4e425bdcc..abf5feebb 100644
--- a/browser_tests/fixtures/ComfyPage.ts
+++ b/browser_tests/fixtures/ComfyPage.ts
@@ -737,6 +737,19 @@ export class ComfyPage {
     )
   }
 
+  async confirmDialog(prompt: string, text: string = 'Yes') {
+    const modal = this.page.locator(
+      `.comfy-modal-content:has-text("${prompt}")`
+    )
+    await expect(modal).toBeVisible()
+    await modal
+      .locator('.comfyui-button', {
+        hasText: text
+      })
+      .click()
+    await expect(modal).toBeHidden()
+  }
+
   async convertAllNodesToGroupNode(groupNodeName: string) {
     this.page.on('dialog', async (dialog) => {
       await dialog.accept(groupNodeName)
diff --git a/browser_tests/fixtures/components/SidebarTab.ts b/browser_tests/fixtures/components/SidebarTab.ts
index 76b74c6dc..836694be9 100644
--- a/browser_tests/fixtures/components/SidebarTab.ts
+++ b/browser_tests/fixtures/components/SidebarTab.ts
@@ -103,6 +103,12 @@ export class WorkflowsSidebarTab extends SidebarTab {
       .allInnerTexts()
   }
 
+  async getActiveWorkflowName() {
+    return await this.page
+      .locator('.comfyui-workflows-open .p-tree-node-selected .node-label')
+      .innerText()
+  }
+
   async getTopLevelSavedWorkflowNames() {
     return await this.page
       .locator('.comfyui-workflows-browse .node-label')
diff --git a/browser_tests/menu.spec.ts b/browser_tests/menu.spec.ts
index 7349df3cd..3b956a04f 100644
--- a/browser_tests/menu.spec.ts
+++ b/browser_tests/menu.spec.ts
@@ -379,7 +379,9 @@ test.describe('Menu', () => {
       // Open the sidebar
       const tab = comfyPage.menu.workflowsTab
       await tab.open()
+    })
 
+    test.afterEach(async ({ comfyPage }) => {
       await comfyPage.setupWorkflowsDirectory({})
     })
 
@@ -450,6 +452,43 @@ test.describe('Menu', () => {
       ).toEqual(['*Unsaved Workflow.json', 'workflow3.json', 'workflow4.json'])
     })
 
+    test('Can save workflow as with same name', async ({ comfyPage }) => {
+      await comfyPage.menu.topbar.saveWorkflow('workflow5.json')
+      expect(
+        await comfyPage.menu.workflowsTab.getOpenedWorkflowNames()
+      ).toEqual(['workflow5.json'])
+
+      await comfyPage.menu.topbar.saveWorkflowAs('workflow5.json')
+      await comfyPage.confirmDialog('Overwrite existing file?', 'Yes')
+      expect(
+        await comfyPage.menu.workflowsTab.getOpenedWorkflowNames()
+      ).toEqual(['workflow5.json'])
+    })
+
+    test('Can overwrite other workflows with save as', async ({
+      comfyPage
+    }) => {
+      const topbar = comfyPage.menu.topbar
+      await topbar.saveWorkflow('workflow1.json')
+      await topbar.saveWorkflowAs('workflow2.json')
+      expect(
+        await comfyPage.menu.workflowsTab.getOpenedWorkflowNames()
+      ).toEqual(['workflow1.json', 'workflow2.json'])
+      expect(await comfyPage.menu.workflowsTab.getActiveWorkflowName()).toEqual(
+        'workflow2.json'
+      )
+
+      await topbar.saveWorkflowAs('workflow1.json')
+      await comfyPage.confirmDialog('Overwrite existing file?', 'Yes')
+      // The old workflow1.json should be deleted and the new one should be saved.
+      expect(
+        await comfyPage.menu.workflowsTab.getOpenedWorkflowNames()
+      ).toEqual(['workflow2.json', 'workflow1.json'])
+      expect(await comfyPage.menu.workflowsTab.getActiveWorkflowName()).toEqual(
+        'workflow1.json'
+      )
+    })
+
     test('Does not report warning when switching between opened workflows', async ({
       comfyPage
     }) => {
@@ -475,7 +514,7 @@ test.describe('Menu', () => {
         `tempWorkflow-${test.info().title}`
       )
       const closeButton = comfyPage.page.locator(
-        '.comfyui-workflows-open .p-button-icon.pi-times'
+        '.comfyui-workflows-open .close-workflow-button'
       )
       await closeButton.click()
       expect(
diff --git a/src/components/sidebar/tabs/WorkflowsSidebarTab.vue b/src/components/sidebar/tabs/WorkflowsSidebarTab.vue
index 21dae8f44..3f4ad7048 100644
--- a/src/components/sidebar/tabs/WorkflowsSidebarTab.vue
+++ b/src/components/sidebar/tabs/WorkflowsSidebarTab.vue
@@ -54,6 +54,7 @@
                 </template>
                 <template #actions="{ node }">
                   <Button
+                    class="close-workflow-button"
                     icon="pi pi-times"
                     text
                     :severity="
diff --git a/src/services/workflowService.ts b/src/services/workflowService.ts
index bd6355ec3..a5a81d254 100644
--- a/src/services/workflowService.ts
+++ b/src/services/workflowService.ts
@@ -63,17 +63,36 @@ export const workflowService = {
 
     const newPath = workflow.directory + '/' + appendJsonExt(newFilename)
     const newKey = newPath.substring(ComfyWorkflow.basePath.length)
+    const workflowStore = useWorkflowStore()
+    const existingWorkflow = workflowStore.getWorkflowByPath(newPath)
+
+    if (existingWorkflow) {
+      const res = (await ComfyAsyncDialog.prompt({
+        title: 'Overwrite existing file?',
+        message: `"${newPath}" already exists. Do you want to overwrite it?`,
+        actions: ['Yes', 'No']
+      })) as 'Yes' | 'No'
+
+      if (res === 'No') return
+
+      if (existingWorkflow.path === workflow.path) {
+        await this.saveWorkflow(workflow)
+        return
+      }
+      const deleted = await this.deleteWorkflow(existingWorkflow)
+      if (!deleted) return
+    }
 
     if (workflow.isTemporary) {
       await this.renameWorkflow(workflow, newPath)
-      await useWorkflowStore().saveWorkflow(workflow)
+      await workflowStore.saveWorkflow(workflow)
     } else {
-      const tempWorkflow = useWorkflowStore().createTemporary(
+      const tempWorkflow = workflowStore.createTemporary(
         newKey,
         workflow.activeState as ComfyWorkflowJSON
       )
       await this.openWorkflow(tempWorkflow)
-      await useWorkflowStore().saveWorkflow(tempWorkflow)
+      await workflowStore.saveWorkflow(tempWorkflow)
     }
   },
 
@@ -131,9 +150,9 @@ export const workflowService = {
   async closeWorkflow(
     workflow: ComfyWorkflow,
     options: { warnIfUnsaved: boolean } = { warnIfUnsaved: true }
-  ): Promise<void> {
+  ): Promise<boolean> {
     if (!workflow.isLoaded) {
-      return
+      return true
     }
 
     if (workflow.isModified && options.warnIfUnsaved) {
@@ -146,7 +165,7 @@ export const workflowService = {
       if (res === 'Yes') {
         await this.saveWorkflow(workflow)
       } else if (res === 'Cancel') {
-        return
+        return false
       }
     }
 
@@ -161,18 +180,26 @@ export const workflowService = {
     }
 
     await workflowStore.closeWorkflow(workflow)
+    return true
   },
 
   async renameWorkflow(workflow: ComfyWorkflow, newPath: string) {
     await useWorkflowStore().renameWorkflow(workflow, newPath)
   },
 
-  async deleteWorkflow(workflow: ComfyWorkflow) {
+  /**
+   * Delete a workflow
+   * @param workflow The workflow to delete
+   * @returns true if the workflow was deleted, false if the user cancelled
+   */
+  async deleteWorkflow(workflow: ComfyWorkflow): Promise<boolean> {
     const workflowStore = useWorkflowStore()
     if (workflowStore.isOpen(workflow)) {
-      await this.closeWorkflow(workflow)
+      const closed = await this.closeWorkflow(workflow)
+      if (!closed) return false
     }
     await workflowStore.deleteWorkflow(workflow)
+    return true
   },
 
   /**