Images shown by state-run television KRT on Saturday showed the leader accompanied by military officials as he watched the contest from an elevated viewing platform.
The images showed tanks driving over obstacles and firing at distant targets.
Hwang Pyong So, director of the General Political Bureau of the Korean People’s Army (KPA) and Ri Myong Su, chief of the general staff of the KPA, were among the senior officers watching the contest.
KRT did not say where or when the competition took place.
It comes after the US imposed sanctions on 11 North Koreans and one North Korean company over links to the country’s weapons programmes, banks and commodities trade.
US Defense Secretary Jim Mattis accused Pyongyang of acting in a reckless manner and said it had to be stopped during a joint news conference with British Defence Secretary Michael Fallon on Friday.
The body of Kim Jong-Nam, the North Korean leader’s half-brother, was returned on Friday after he was poisoned by VX nerve agent at Kuala Lumpur airport.