diff --git a/src/checkstyle/checkstyle.xml b/src/checkstyle/checkstyle.xml
index d7ba423332f..a0e0b8d47f4 100644
--- a/src/checkstyle/checkstyle.xml
+++ b/src/checkstyle/checkstyle.xml
@@ -107,7 +107,7 @@
 			<property name="id" value="bannedImports"/>
 			<property name="regexp" value="true"/>
 			<property name="illegalClasses"
-				value="^reactor\.core\.support\.Assert,^org\.slf4j\.LoggerFactory,^(?!org\.jspecify|\.annotations).*(NonNull|Nullable)$"/>
+				value="^reactor\.core\.support\.Assert,^org\.slf4j\.LoggerFactory,^(?!org\.jspecify|\.annotations).*(NonNull|Nullable),^org\.jetbrains\.annotations\.Nullable$"/>
 		</module>
 		<module name="com.puppycrawl.tools.checkstyle.checks.imports.IllegalImportCheck">
 			<property name="id" value="bannedJUnit3Imports"/>