This study determined the effect of computer assisted instruction on the academic performance of agricultural Science students in Kaduna State College of Education Gidan-Waya, Kaduna State Nigeria. The study had four specific objectives.Four research questions stated and four research hypotheses were formulated and tested at 0.05 level of significance. The design adopted for the research was quasi pretest-post-test, experimental design.The population comprisedof sixty one (61) students of NCE II 2015/2016 sessionwho offered courses in agricultural education. The experimental groups were made up of 10 students exposed to computer assisted instruction Package (CAI) for seven weeks while the control was a group of 10 students who were taught using conventional lecture method for seven weeks. An instrument consisting of 20 objective questions and two essay questions agricultural science achievement test (ASAT) with reliability of 0.85 was administered during post-test.Data were analyzed using mean, standard deviation and t-test statistic. The findings of the study revealed there was significant difference in objective test of students taught with CAI than those in the control group.It also showed a significant difference between the academic performances of students taught using CAI and those in the control group. The study further showed that their was significant difference in the academic performance of students taught using CAI based on gender with mean scores for both experimental and control group were 41.60 and 48.00 in favour of female students.The researcher concluded that CAI produced better result than the conventional teaching methods.It is recommendedthat CAI should be used in teaching of agricultural science in colleges of education, and that teachers be provided with modern computers and software's necessary to teach agricultural science.