diff --git a/src/main/java/org/codelibs/fess/app/web/admin/badword/CreateForm.java b/src/main/java/org/codelibs/fess/app/web/admin/badword/CreateForm.java
index d6f644c3c..7c49fbf0a 100644
--- a/src/main/java/org/codelibs/fess/app/web/admin/badword/CreateForm.java
+++ b/src/main/java/org/codelibs/fess/app/web/admin/badword/CreateForm.java
@@ -15,6 +15,7 @@
  */
 package org.codelibs.fess.app.web.admin.badword;
 
+import javax.validation.constraints.Pattern;
 import javax.validation.constraints.Size;
 
 import org.codelibs.fess.util.ComponentUtil;
@@ -31,6 +32,7 @@ public class CreateForm {
     public Integer crudMode;
 
     @Required
+    @Pattern(regexp = "[^\\s]+")
     public String suggestWord;
 
     @Size(max = 1000)