Julius Kariuki (born June 12, 1961) was the winner of the 3000 m steeplechase at the 1988 Summer Olympics.

Born in Nyahururu , Kenya, Kariuki's athletic career started slowly. He made his international debut at the 1984 Summer Olympics, where he finished seventh in the 3000 m steeplechase.

The following year, Kariuki won the steeplechase at the African Championships, and then followed that up with a victory in a slow race at the IAAF World Cup . At the Seoul Olympics, Kariuki was mostly considered as the third-string Kenyan runner, but in the final, after a very fast start, Kariuki and his fellow countryman Peter Koech broke clear, and a lap later, Kariuki sped away from his more experienced teammate, and went on to win the gold medal.

In 1989, Kariuki won the 10,000 m at the World Student Games and the 3000 m steeplechase again in the IAAF Word Cup. In 1990, he won gold easily at the Commonwealth Games and finished fourth at the following year's World Championships. Kariuki remained one of the world's top steeplechasers for several more years after that, but the dominance of Kenyan talent was so great, that he was never able again to gain representation on the national team to a major international championship.