diff --git a/spa/include/spa/utils/json.h b/spa/include/spa/utils/json.h
index b3e69eaa7..617c70fab 100644
--- a/spa/include/spa/utils/json.h
+++ b/spa/include/spa/utils/json.h
@@ -389,6 +389,7 @@ static inline int spa_json_encode_string(char *str, int size, const char *val)
 			break;
 		case '\\':
 		case '"':
+		case '/':
 			__PUT('\\'); __PUT(*val);
 			break;
 		default: