diff --git a/src/__tests__/opencode_cell_actions.spec.ts b/src/__tests__/opencode_cell_actions.spec.ts
index b16d36e..9ac2e0c 100644
--- a/src/__tests__/opencode_cell_actions.spec.ts
+++ b/src/__tests__/opencode_cell_actions.spec.ts
@@ -619,4 +619,59 @@ describe('OpenCodeInlinePrompt', () => {
     const writeText = (navigator.clipboard.writeText as unknown as jest.Mock);
     expect(writeText).toHaveBeenCalledWith('print(1)');
   });
+
+  it('Enter in the textarea submits; Shift+Enter does not', () => {
+    const cell = makeFakeCell('x = 1');
+    const onSubmit = jest.fn();
+    const prompt = new OpenCodeInlinePrompt(cell, {
+      onSubmit,
+      onCancel: jest.fn(),
+      disabled: false,
+      providers: null
+    });
+    prompt.setMessages([
+      { role: 'user', content: '' },
+      { role: 'assistant', content: 'noop' }
+    ]);
+    const textarea = prompt.node.querySelector(
+      'textarea'
+    ) as HTMLTextAreaElement;
+    textarea.value = 'fix the bug';
+
+    // Plain Enter submits with the current text + the current
+    // provider/model selection (both default to "" / first when null).
+    textarea.dispatchEvent(
+      new KeyboardEvent('keydown', {
+        key: 'Enter',
+        bubbles: true,
+        cancelable: true
+      })
+    );
+    expect(onSubmit).toHaveBeenCalledTimes(1);
+    expect(onSubmit).toHaveBeenCalledWith('fix the bug', undefined, undefined);
+
+    // Shift+Enter must NOT submit (chat convention: newline).
+    onSubmit.mockClear();
+    textarea.dispatchEvent(
+      new KeyboardEvent('keydown', {
+        key: 'Enter',
+        shiftKey: true,
+        bubbles: true,
+        cancelable: true
+      })
+    );
+    expect(onSubmit).not.toHaveBeenCalled();
+
+    // Ctrl+Enter also must not submit (newline).
+    onSubmit.mockClear();
+    textarea.dispatchEvent(
+      new KeyboardEvent('keydown', {
+        key: 'Enter',
+        ctrlKey: true,
+        bubbles: true,
+        cancelable: true
+      })
+    );
+    expect(onSubmit).not.toHaveBeenCalled();
+  });
 });
diff --git a/src/components/opencode_inline_prompt.ts b/src/components/opencode_inline_prompt.ts
index a4fdc6c..f7328e0 100644
--- a/src/components/opencode_inline_prompt.ts
+++ b/src/components/opencode_inline_prompt.ts
@@ -125,6 +125,14 @@ export class OpenCodeInlinePrompt extends Widget {
       const modelId = this._modelSelect?.value || undefined;
       options.onSubmit(text, providerId, modelId);
     });
+    // Chat-input convention: Enter submits, Shift+Enter / Ctrl+Enter
+    // insert a newline (textarea default).
+    this._textarea.addEventListener('keydown', (e) => {
+      if (e.key === 'Enter' && !e.shiftKey && !e.ctrlKey) {
+        e.preventDefault();
+        this._sendBtn.click();
+      }
+    });
     this._cancelBtn = document.createElement('button');
     this._cancelBtn.className = 'opencode-btn-cancel';
     this._cancelBtn.textContent = '取消';