diff --git a/source3/registry/reg_format.h b/source3/registry/reg_format.h
index 5d0a4f25364..e4e59d79fd1 100644
--- a/source3/registry/reg_format.h
+++ b/source3/registry/reg_format.h
@@ -52,7 +52,7 @@ struct regval_blob;
 typedef struct reg_format reg_format;
 
 /**
- * Protoype for function called to output a line.
+ * Prototype for function called to output a line.
  *
  * @param private_data
  * @param line line to write in UNIX charset