diff --git a/NEWS b/NEWS
index 692a2ae52b2..18851577a35 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,9 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.5.5
 
+- Opcache:
+  . Fixed bug GH-21052 (Preloaded constant erroneously propagated to file-cached
+    script). (ilutov)
 
 12 Mar 2026, PHP 8.5.4
 
diff --git a/Zend/Optimizer/zend_optimizer.c b/Zend/Optimizer/zend_optimizer.c
index 80eabe97c32..d3a43617e92 100644
--- a/Zend/Optimizer/zend_optimizer.c
+++ b/Zend/Optimizer/zend_optimizer.c
@@ -779,6 +779,9 @@ static bool zend_optimizer_ignore_class(zval *ce_zv, zend_string *filename)
 	zend_class_entry *ce = Z_PTR_P(ce_zv);
 
 	if (ce->ce_flags & ZEND_ACC_PRELOADED) {
+		if (CG(compiler_options) & ZEND_COMPILE_WITH_FILE_CACHE) {
+			return true;
+		}
 		Bucket *ce_bucket = (Bucket*)((uintptr_t)ce_zv - XtOffsetOf(Bucket, val));
 		size_t offset = ce_bucket - EG(class_table)->arData;
 		if (offset < EG(persistent_classes_count)) {
@@ -797,6 +800,9 @@ static bool zend_optimizer_ignore_function(zval *fbc_zv, zend_string *filename)
 		return false;
 	} else if (fbc->type == ZEND_USER_FUNCTION) {
 		if (fbc->op_array.fn_flags & ZEND_ACC_PRELOADED) {
+			if (CG(compiler_options) & ZEND_COMPILE_WITH_FILE_CACHE) {
+				return true;
+			}
 			Bucket *fbc_bucket = (Bucket*)((uintptr_t)fbc_zv - XtOffsetOf(Bucket, val));
 			size_t offset = fbc_bucket - EG(function_table)->arData;
 			if (offset < EG(persistent_functions_count)) {
diff --git a/ext/opcache/tests/gh21052.phpt b/ext/opcache/tests/gh21052.phpt
new file mode 100644
index 00000000000..d9d0430b9ee
--- /dev/null
+++ b/ext/opcache/tests/gh21052.phpt
@@ -0,0 +1,32 @@
+--TEST--
+GH-21052: Preloaded constant erroneously propagated to file-cached script
+--CREDITS--
+Grummfy
+--EXTENSIONS--
+opcache
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.file_cache="{TMP}"
+opcache.preload={PWD}/gh21052_a.inc
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY == 'Windows') die('skip Preloading is not supported on Windows');
+?>
+--FILE--
+<?php
+require __DIR__ . '/gh21052_b.inc';
+?>
+--EXPECT--
+array(1) {
+  [0]=>
+  string(3) "foo"
+}
+array(1) {
+  [0]=>
+  string(3) "foo"
+}
+array(1) {
+  [0]=>
+  string(3) "foo"
+}
diff --git a/ext/opcache/tests/gh21052_a.inc b/ext/opcache/tests/gh21052_a.inc
new file mode 100644
index 00000000000..f9614369798
--- /dev/null
+++ b/ext/opcache/tests/gh21052_a.inc
@@ -0,0 +1,13 @@
+<?php
+
+class A {
+    const C = ['foo'];
+
+    public static function test() {
+        return ['foo'];
+    }
+}
+
+function test() {
+    return ['foo'];
+}
diff --git a/ext/opcache/tests/gh21052_b.inc b/ext/opcache/tests/gh21052_b.inc
new file mode 100644
index 00000000000..cb64924ed5a
--- /dev/null
+++ b/ext/opcache/tests/gh21052_b.inc
@@ -0,0 +1,5 @@
+<?php
+
+var_dump(A::C);
+var_dump(A::test());
+var_dump(test());