Transfer of motor learning referred to the impact of previous experiences on performing a skill in a new context or on learning a new skill. Since Thorndike (1914) proposed the theory of identical elements, the research from both motor and verbal learning has produced a great deal of information on transfer effects. However, what accounts for the transfer phenomenon remains unknown. The purpose of the present study was to investigate whether practicing complex movement enhanced transfer of learning compared to practicing simple movement. In order to test the hypothesis, a motor learning experiment was conduct in a soundproof room. The participants (n=20) were randomly assigned into one of the two practice groups (simple or complex). For the simple condition, the participants performed a typical choice reaction time (RT) task with four different colors as stimuli and pressing the keys matched as responses. The complex condition asked the participants to subsequently press three additional keys with clockwise direction after the choice RT task. The both groups were assessed in two transfer tests with simple task transfer (different matching between colors and keys) and complex task transfer (different order for pressing subsequent keys). The results demonstrated complex condition produced higher choice RT than simple condition during the practice, F (1, 18) = 5.78, p<.01. However, during the transfer tests, complex practice group demonstrated significantly lower choice RT in simple task transfer [F (1, 18) = 10.58, p<.01] and complex task transfer [F (1, 18) = 4.72, p<.05] compared to simple practice group. It indicates practicing a complex movement enhances transfer of learning relative to practicing a simple movement. The present finding was supported by the recent advance in animal motor learning, which found only complex motor learning increased synaptic connections in the brain.Keyword(s): performance, physical activity, research