diff --git a/news/11935.feature.rst b/news/11935.feature.rst
new file mode 100644
index 00000000000..b170ca1d8cd
--- /dev/null
+++ b/news/11935.feature.rst
@@ -0,0 +1 @@
+Warn if ``--hash`` is used on a line without requirement in a requirements file.
diff --git a/src/pip/_internal/req/req_file.py b/src/pip/_internal/req/req_file.py
index aced95e64c4..8428888d932 100644
--- a/src/pip/_internal/req/req_file.py
+++ b/src/pip/_internal/req/req_file.py
@@ -2,6 +2,7 @@
 Requirements file parsing
 """
 
+import logging
 import optparse
 import os
 import re
@@ -76,6 +77,8 @@
 # the 'dest' string values
 SUPPORTED_OPTIONS_REQ_DEST = [str(o().dest) for o in SUPPORTED_OPTIONS_REQ]
 
+logger = logging.getLogger(__name__)
+
 
 class ParsedRequirement:
     def __init__(
@@ -209,6 +212,13 @@ def handle_option_line(
     options: Optional[optparse.Values] = None,
     session: Optional[PipSession] = None,
 ) -> None:
+    if opts.hashes:
+        logger.warning(
+            "%s line %s has --hash but no requirement, and will be ignored.",
+            filename,
+            lineno,
+        )
+
     if options:
         # percolate options upward
         if opts.require_hashes: