diff --git a/docs/Manpage.md b/docs/Manpage.md
index 12b9f20c17..eedda4456f 100644
--- a/docs/Manpage.md
+++ b/docs/Manpage.md
@@ -2037,6 +2037,9 @@ example, run `export HOMEBREW_NO_INSECURE_REDIRECT=1` rather than just
 - `HOMEBREW_NO_INSTALLED_DEPENDENTS_CHECK`
   <br>If set, do not check for broken dependents after installing, upgrading or reinstalling formulae.
 
+- `HOMEBREW_NO_CLEANUP_FORMULAE`
+  <br>A comma-separated list of formulae. Homebrew will refuse to clean up a formula if it appears on this list.
+
 - `HOMEBREW_NO_COLOR`
   <br>If set, do not print text with colour added.
 
diff --git a/manpages/brew.1 b/manpages/brew.1
index 3586e59ecf..3274b4ad2b 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -2943,6 +2943,12 @@ If set, do not use Bootsnap to speed up repeated \fBbrew\fR calls\.
 If set, do not check for broken dependents after installing, upgrading or reinstalling formulae\.
 .
 .TP
+\fBHOMEBREW_NO_CLEANUP_FORMULAE\fR
+.
+.br
+A comma\-separated list of formulae\. Homebrew will refuse to clean up a formula if it appears on this list\.
+.
+.TP
 \fBHOMEBREW_NO_COLOR\fR
 .
 .br