diff --git a/src/_pytest/mark/expression.py b/src/_pytest/mark/expression.py
index 83ff25ffc..9d57e944b 100644
--- a/src/_pytest/mark/expression.py
+++ b/src/_pytest/mark/expression.py
@@ -88,7 +88,7 @@ class Scanner:
                 yield Token(TokenType.RPAREN, ")", pos)
                 pos += 1
             else:
-                match = re.match(r"(:?\w|:|\+|-|\.|\[|\]|\\|\/)+", input[pos:])
+                match = re.match(r"(:?\w|:|\+|-|\.|\[|\]|\\|/)+", input[pos:])
                 if match:
                     value = match.group(0)
                     if value == "or":