diff --git a/modules/javafx.graphics/src/main/java/javafx/scene/shape/Box.java b/modules/javafx.graphics/src/main/java/javafx/scene/shape/Box.java
index 260a5dfd939..d365f221929 100644
--- a/modules/javafx.graphics/src/main/java/javafx/scene/shape/Box.java
+++ b/modules/javafx.graphics/src/main/java/javafx/scene/shape/Box.java
@@ -85,6 +85,11 @@ public boolean doComputeIntersects(Node node, PickRay pickRay,
 
     private TriangleMesh mesh;
 
+    /**
+     * Default size of the {@code Box}.
+     * @deprecated This field was exposed mistakenly and will be removed.
+     */
+    @Deprecated(since = "18", forRemoval = true)
     public static final double DEFAULT_SIZE = 2;
 
     {