Jack Clarke was a New Zealand long-distance athlete who won a bronze medal representing his country in the marathon at the 1950 British Empire Games.

[2] In 1948, Clarke won the marathon at the New Zealand athletic championships held in Dunedin, recording 2:44:06, the second-fastest winning time in the championship's history at the time.

[3] Despite not completing the marathon course at the 1950 national championships in Napier, Clarke was one of four runners selected to represent New Zealand in the marathon at the 1950 British Empire Games the following month in Auckland.

[1] In that event, Clarke won the bronze medal in a time of 2:39:26,[4] despite having a large dog snapping angrily at his heels at one stage of the race.

[6] Clarke was farm manager for the Roydon Lodge Stud, established by John McKenzie in 1927, at Yaldhurst on the western outskirts of Christchurch.