Abstract: The problem in this research is that some athletes have maximum speed and strength in this research and some athletes still see that the strength and speed in kicking is not maximal so that the opponent is easy to avoid, the kick of Mawashi Gery of a karate athlete should be fast and strong. in motion so that the opponent is difficult to hold and avoid. The purpose of this study was to determine whether there is a relationship between leg muscle power and reaction time to Mawashi Gery's kick on the Karateka Putra Dojo Lemkari Kuantan Singingi, totaling 13 people. The sampling technique is total sampling where all populations are sampled. The instruments used in this study were leg muscle power test, reaction time test and mawashi gery kick speed test. Data obtained from statistical analysis of product moment correlation. Based on the results of research and data processing using statistical research procedures, the data normality test analysis on variable X1 (leg muscle power) produces Lhitung of 0.120 and Ltabel of 0.234, meaning Lhitung ttable (0.576), where Ha was accepted and Ho was rejected, it could be concluded that there was a relationship between leg muscle power and reaction time to Mawashi Gery's kick at Karateka Putra Dojo Lemkari Kuantan Singingi.Key Words: Leg Muscle Power, Reaction Time And Kick Speed Of Mawashi Gery