diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -4556,6 +4556,12 @@
             _(b'BRANCH'),
         ),
         (
+            b'B',
+            b'bookmark',
+            [],
+            _(b"show changesets within the given bookmark"),
+            _(b'BOOKMARK')),
+        (
             b'P',
             b'prune',
             [],
diff --git a/mercurial/logcmdutil.py b/mercurial/logcmdutil.py
--- a/mercurial/logcmdutil.py
+++ b/mercurial/logcmdutil.py
@@ -774,6 +774,7 @@
     b'_matchfiles': (None, b'_matchfiles(%ps)'),
     b'date': (b'date(%s)', None),
     b'branch': (b'branch(%s)', b'%lr'),
+    b'bookmark': (b'reverse(ancestors(bookmark(%s)))', b'%lr'),
     b'_patslog': (b'filelog(%s)', b'%lr'),
     b'keyword': (b'keyword(%s)', b'%lr'),
     b'prune': (b'ancestors(%s)', b'not %lr'),