diff --git a/man7/system_data_types.7 b/man7/system_data_types.7
index ddabefd16..fc9893e41 100644
--- a/man7/system_data_types.7
+++ b/man7/system_data_types.7
@@ -85,6 +85,25 @@ POSIX.1-2001 and later.
 .BR aio_write (3),
 .BR lio_listio (3)
 .RE
+.\"------------------------------------- blkcnt_t ---------------------/
+.TP
+.I blkcnt_t
+.RS
+.IR Include :
+.IR <sys/types.h> .
+Alternatively,
+.IR <sys/stat.h> .
+.PP
+Used for file block counts.
+According to POSIX,
+it shall be a signed integer type.
+.PP
+.IR "Conforming to" :
+POSIX.1-2001 and later.
+.PP
+.IR "See also" :
+.BR stat (2)
+.RE
 .\"------------------------------------- clock_t ----------------------/
 .TP
 .I clock_t