diff --git a/docs/Manpage.md b/docs/Manpage.md
index 19350e83d0..cc87074b45 100644
--- a/docs/Manpage.md
+++ b/docs/Manpage.md
@@ -2195,6 +2195,11 @@ example, run `export HOMEBREW_NO_INSECURE_REDIRECT=1` rather than just
 - `HOMEBREW_NO_INSTALL_UPGRADE`
   <br>If set, `brew install *`formula`*` will not upgrade `*`formula`*` if it is installed but outdated.
 
+- `HOMEBREW_PIP_INDEX_URL`
+  <br>If set, `brew install *`formula`*` will use this URL to download PyPI package resources.
+
+  *Default:* `https://pypi.org/simple`.
+
 - `HOMEBREW_PRY`
   <br>If set, use Pry for the `brew irb` command.
 
diff --git a/manpages/brew.1 b/manpages/brew.1
index bec8a19d20..add3c39520 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -3225,6 +3225,15 @@ If set, \fBbrew install\fR, \fBbrew upgrade\fR and \fBbrew reinstall\fR will nev
 If set, \fBbrew install <formula>\fR will not upgrade \fB<formula>\fR if it is installed but outdated\.
 .
 .TP
+\fBHOMEBREW_PIP_INDEX_URL\fR
+.
+.br
+If set, \fBbrew install <formula>\fR will use this URL to download PyPI package resources\.
+.
+.IP
+\fIDefault:\fR \fBhttps://pypi\.org/simple\fR\.
+.
+.TP
 \fBHOMEBREW_PRY\fR
 .
 .br