diff --git a/grammar/README.md b/grammar/README.md
index 105de2cbe4..b15b36e3ab 100644
--- a/grammar/README.md
+++ b/grammar/README.md
@@ -1627,7 +1627,7 @@ Go to: _[expression](#user-content-expression)_;
 
 <a name="print-function"></a>
 ```abnf
-print-function = %s"debug" / %s"error" / %s"log"
+print-function = %s"error" / %s"log"
 ```
 
 <a name="print-arguments"></a>
diff --git a/grammar/abnf-grammar.txt b/grammar/abnf-grammar.txt
index af4bd430a1..092a7f13fd 100644
--- a/grammar/abnf-grammar.txt
+++ b/grammar/abnf-grammar.txt
@@ -971,7 +971,7 @@ console-call = assert-call
 
 assert-call = %s"assert" "(" expression ")"
 
-print-function = %s"debug" / %s"error" / %s"log"
+print-function = %s"error" / %s"log"
 
 print-arguments = "(" string-literal  *( "," expression ) ")"