diff --git a/git-series.1 b/git-series.1
index 5a29808f37f1bcba3f81516fe3b5e4ec53843d9e..9ed197c7510045acfdf38cec7ab6f446ad42dce8 100644
--- a/git-series.1
+++ b/git-series.1
@@ -134,7 +134,7 @@ the commits.
 [\fB-v\fR \fIN\fR | \fB--reroll-count=\fR\fIN\fR] \
 [\fB--rfc\fR] \
 [\fB--stdout\fR] \
-[\fB--subject-prefix=\fR\fISubject-Prefix\fR]
+[\fB--subject-prefix=\fR\fIprefix\fR]
 Prepare the patch series to send via email.
 This creates one file per patch in the series, plus one additional file for the
 cover letter if any.
@@ -172,8 +172,8 @@ Use [RFC PATCH] instead of the standard [PATCH] prefix.
 .B --stdout
 Write the entire patch series to stdout rather than to separate patch files.
 .TP
-.BI --subject-prefix= Subject-Prefix
-Use [\fISubject-Prefix\fR] instead of the standard [PATCH] prefix.
+.BI --subject-prefix= prefix
+Use [\fIprefix\fR] instead of the standard [PATCH] prefix.
 .RE
 
 .TP
diff --git a/src/main.rs b/src/main.rs
index e02a80f82decd6d5057533a354960c2a64448b4a..056f709b8caba2a4c8a34a5670ee00c63e791c55 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1981,7 +1981,7 @@ fn main() {
                     .arg_from_usage("-v, --reroll-count=[N] 'Mark the patch series as PATCH vN'")
                     .arg(Arg::from_usage("--rfc 'Use [RFC PATCH] instead of the standard [PATCH] prefix'").conflicts_with("subject-prefix"))
                     .arg_from_usage("--stdout 'Write patches to stdout rather than files'")
-                    .arg_from_usage("--subject-prefix [Subject-Prefix] 'Use [Subject-Prefix] instead of the standard [PATCH] prefix'"),
+                    .arg_from_usage("--subject-prefix [prefix] 'Use [prefix] instead of the standard [PATCH] prefix'"),
                 SubCommand::with_name("log")
                     .about("Show the history of the patch series")
                     .arg_from_usage("-p, --patch 'Include a patch for each change committed to the series'"),