The purpose of this study was to examine the effects of teacher mediation on the mathematics learning of kindergarten students in a computer-assisted learning environment. A sample of 26 students was randomly selected and assigned into experimental and control groups. The experimental group was mediated by a teacher during the computer-assisted learning activity. The control group received no teacher mediation. Data were collected for both groups for activity enjoyment and mathematics learning experience at the end of 6 weeks. Data were analyzed using independent t-tests at a 0.05 level of significance. The results indicated a significant difference between experimental and control groups on levels of activity enjoyment. The experimental group showed higher levels of enjoyment compared to the control group. No significant difference was found in mathematics learning between the experimental and control group. The results on mathematics learning were not congruent with literature review. Further research is recommended. (Contains 1 table.)