From 8fd30ab4a201e167fb2c88723feb8752ee845803 Mon Sep 17 00:00:00 2001
From: QdabuliuQ <69883552+QdabuliuQ@users.noreply.github.com>
Date: Tue, 13 Jan 2026 18:14:54 +0800
Subject: [PATCH] fix(Button): child element's className being cleared when
 rendering two Chinese characters. (#56593)

---
 components/button/__tests__/index.test.tsx | 17 +++++++++++++++++
 components/button/buttonHelpers.tsx        |  4 ++--
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/components/button/__tests__/index.test.tsx b/components/button/__tests__/index.test.tsx
index 9b73a56c2d..3d34dc005e 100644
--- a/components/button/__tests__/index.test.tsx
+++ b/components/button/__tests__/index.test.tsx
@@ -115,6 +115,23 @@ describe('Button', () => {
     expect(container.querySelector('.ant-btn')).toHaveClass('ant-btn-two-chinese-chars');
   });
 
+  // https://github.com/ant-design/ant-design/issues/56591
+  it('should preserve className when rendering two Chinese characters in child element', () => {
+    const { container } = render(
+      <Button>
+        <span className="custom-class" style={{ color: 'rgb(255, 0, 0)' }}>
+          按钮
+        </span>
+      </Button>,
+    );
+
+    const span = container.querySelector('span.custom-class');
+    expect(span).toBeTruthy();
+    expect(span).toHaveClass('custom-class');
+    expect(span).toHaveStyle({ color: 'rgb(255, 0, 0)' });
+    expect(span).toHaveTextContent('按 钮');
+  });
+
   // https://github.com/ant-design/ant-design/issues/18118
   it('should not insert space to link or text button', () => {
     const wrapper1 = render(<Button type="link">按钮</Button>);
diff --git a/components/button/buttonHelpers.tsx b/components/button/buttonHelpers.tsx
index 06ee6ec218..8522661e5c 100644
--- a/components/button/buttonHelpers.tsx
+++ b/components/button/buttonHelpers.tsx
@@ -54,8 +54,8 @@ function splitCNCharsBySpace(
     return cloneElement(child, (oriProps) => ({
       ...oriProps,
       children: oriProps.children.split('').join(SPACE),
-      className,
-      style,
+      className: clsx(oriProps.className, className) || undefined,
+      style: { ...oriProps.style, ...style },
     }));
   }