diff --git a/man/man1/openmc.1 b/man/man1/openmc.1
index 1614e4875..fb0fdd717 100644
--- a/man/man1/openmc.1
+++ b/man/man1/openmc.1
@@ -24,6 +24,9 @@ Run in plotting mode
 Restart a previous run from a state point or a particle restart file named
 \fIbinaryFile\fP.
 .TP
+.BI \-s " N" "\fR,\fP \-\-threads" " N"
+Use \fIN\fP OpenMP threads.
+.TP
 .B "\-v\fR, \fP\-\-version"
 Show version information.
 .TP