diff --git a/pkg/analysis_server/lib/src/domains/analysis/occurrences_dart.dart b/pkg/analysis_server/lib/src/domains/analysis/occurrences_dart.dart
index 99d83c7a7fd..0e47149ac96 100644
--- a/pkg/analysis_server/lib/src/domains/analysis/occurrences_dart.dart
+++ b/pkg/analysis_server/lib/src/domains/analysis/occurrences_dart.dart
@@ -250,7 +250,9 @@ class DartUnitOccurrencesComputerVisitor extends GeneralizingAstVisitor<void> {
 
   @override
   void visitImportPrefixReference(ImportPrefixReference node) {
-    _addOccurrence(node.element!, node.name);
+    if (node.element case var element?) {
+      _addOccurrence(element, node.name);
+    }
 
     super.visitImportPrefixReference(node);
   }
diff --git a/pkg/analysis_server/test/analysis/notification_occurrences_test.dart b/pkg/analysis_server/test/analysis/notification_occurrences_test.dart
index 43d834741a0..4652d6b5a64 100644
--- a/pkg/analysis_server/test/analysis/notification_occurrences_test.dart
+++ b/pkg/analysis_server/test/analysis/notification_occurrences_test.dart
@@ -646,6 +646,15 @@ void foo() {}
 ''');
   }
 
+  Future<void> test_prefix_null() async {
+    // Note, we use `core` just to have some prefix.
+    // The actual check is no crash on unresolved `prefix`.
+    await assertOccurrences(kind: ElementKind.PREFIX, '''
+import 'dart:core' as /*[0*/core/*0]*/;
+void f(prefix.A? _, /*[1*/core.int/*1]*/ _) {}
+''');
+  }
+
   Future<void> test_prefix_wildcard() async {
     // Ensure no crash.
     await assertOccurrences(kind: ElementKind.PREFIX, '''