diff --git a/app/Http/Controllers/Business/Pages.php b/app/Http/Controllers/Business/Pages.php
index 7f5527ed..5a6e7875 100644
--- a/app/Http/Controllers/Business/Pages.php
+++ b/app/Http/Controllers/Business/Pages.php
@@ -1207,8 +1207,9 @@ class Pages extends Controller
                     if ($key === 'remark') {
                         $value = self::receiptDifferenceRemark($row) ?? '';
                     }
-                    // 未匹配行（差额为空）按比对基准金额=0 计入差额，与页面口径一致
-                    if ($key === 'difference' && $value === null) {
+                    // 未匹配行（差额为空）按比对基准金额=0 计入差额，与页面口径一致。
+                    // 注意：上面取值用了 ?? ''，空差值是空字符串而不是 null，这里两种都要认。
+                    if ($key === 'difference' && ($value === null || $value === '')) {
                         $value = round(
                             (float) ($row->income_amount ?? 0) + (float) ($row->discount_amount ?? 0) + (float) ($row->offset_amount ?? 0),
                             2