diff --git a/.jules/palette.md b/.jules/palette.md
index 0bbf5248..502f5a55 100644
--- a/.jules/palette.md
+++ b/.jules/palette.md
@@ -115,3 +115,7 @@
 ## $(date +%Y-%m-%d) - Prevent accidental data loss in inline editors
 **Learning:** Forms that take a long time to fill out (like a WBS editor) are prone to accidental closure by users pressing `Escape` or clicking cancel. This causes immediate data loss without any warning, resulting in frustration.
 **Action:** When working on editors that can be dismissed, track whether the user has modified any fields compared to their initial state. If there are changes, intercept the close action and present a confirmation dialog (`window.confirm`) to ensure they really want to discard their edits. Bypass this for intentional saves or explicit data overrides.
+
+## 2024-05-31 - Replace native disabled with aria-disabled for form submit buttons
+**Learning:** When replacing a native `disabled` attribute with `aria-disabled='true'` on a `<button type='submit'>`, the button becomes active in the DOM and will trigger native HTML5 form validation popups and `submit` events when clicked. This can cause confusing validation popups and unintended execution.
+**Action:** Explicitly check the `aria-disabled` attribute and call `event.preventDefault()` on both the form's `submit` event and the button's `click` event to prevent unintended execution and native validation popups, while preserving focusability.
diff --git a/app.js b/app.js
index a04aae71..abc69203 100644
--- a/app.js
+++ b/app.js
@@ -429,6 +429,11 @@ function bindTableEvents(renderDraftValidation, updateEditorDraftFromEvent) {
       return;
     }
     event.preventDefault();
+    const saveButton = form.querySelector('button[type="submit"]');
+    if (saveButton && saveButton.getAttribute('aria-disabled') === 'true') {
+      showToast('입력값을 올바르게 수정해야 저장할 수 있습니다.');
+      return;
+    }
     renderDraftValidation.flush();
     saveEditor();
   });
@@ -822,6 +827,12 @@ function renderEditorRow(anchorId) {
   saveButton.textContent = '저장';
   saveButton.title = '저장 (Enter)';
   saveButton.setAttribute('aria-keyshortcuts', 'Enter');
+  saveButton.addEventListener('click', (event) => {
+    if (saveButton.getAttribute('aria-disabled') === 'true') {
+      event.preventDefault();
+      event.target.closest('form').dispatchEvent(new Event('submit', { bubbles: true, cancelable: true }));
+    }
+  });
   const cancelButton = document.createElement('button');
   cancelButton.type = 'button';
   cancelButton.className = 'secondary-button';
@@ -1068,7 +1079,11 @@ function renderEditorValidation() {
 
   const saveButton = form.querySelector('button[type="submit"]');
   if (saveButton) {
-    saveButton.disabled = errors.length > 0;
+    if (errors.length > 0) {
+      saveButton.setAttribute('aria-disabled', 'true');
+    } else {
+      saveButton.removeAttribute('aria-disabled');
+    }
     saveButton.title = errors.length > 0 ? '입력값을 올바르게 수정해야 저장할 수 있습니다.' : '저장 (Enter)';
   }
 
diff --git a/tests/e2e/aria-disabled-submit.spec.js b/tests/e2e/aria-disabled-submit.spec.js
new file mode 100644
index 00000000..edff5730
--- /dev/null
+++ b/tests/e2e/aria-disabled-submit.spec.js
@@ -0,0 +1,18 @@
+import { expect, test } from '@playwright/test';
+
+test('aria-disabled save remains focusable and explains why activation is blocked', async ({ page }) => {
+  await page.goto('./');
+  await page.getByRole('button', { name: '최상위 작업 추가' }).click();
+
+  const saveButton = page.getByRole('button', { name: '저장', exact: true });
+  await expect(saveButton).toHaveAttribute('aria-disabled', 'true');
+  await saveButton.focus();
+  await expect(saveButton).toBeFocused();
+
+  await saveButton.click({ force: true });
+
+  await expect(page.locator('.editor-panel')).toBeVisible();
+  await expect(page.locator('#toast')).toHaveText('입력값을 올바르게 수정해야 저장할 수 있습니다.');
+  await expect(page.locator('#toast')).toHaveAttribute('role', 'status');
+  await expect(page.locator('#toast')).toHaveClass(/\bshow\b/);
+});
diff --git a/tests/e2e/mobile-validation.spec.js b/tests/e2e/mobile-validation.spec.js
new file mode 100644
index 00000000..4f105cbf
--- /dev/null
+++ b/tests/e2e/mobile-validation.spec.js
@@ -0,0 +1,24 @@
+import { test, expect } from '@playwright/test';
+
+test.use({
+  viewport: { width: 375, height: 812 },
+  isMobile: true,
+  hasTouch: true,
+});
+
+test('mobile layout renders without breaking and aria-disabled save remains focusable and explains why activation is blocked', async ({ page }) => {
+  await page.goto('./');
+  await page.getByRole('button', { name: '최상위 작업 추가' }).click();
+
+  const saveButton = page.getByRole('button', { name: '저장', exact: true });
+  await expect(saveButton).toHaveAttribute('aria-disabled', 'true');
+  await saveButton.focus();
+  await expect(saveButton).toBeFocused();
+
+  await saveButton.click({ force: true });
+
+  await expect(page.locator('.editor-panel')).toBeVisible();
+  await expect(page.locator('#toast')).toHaveText('입력값을 올바르게 수정해야 저장할 수 있습니다.');
+  await expect(page.locator('#toast')).toHaveAttribute('role', 'status');
+  await expect(page.locator('#toast')).toHaveClass(/\bshow\b/);
+});