The purpose of this research was to determine the effectiveness of microteaching practicum to teaching practice exercise in Colleges of Education in Plateau State, Nigeria. To achieve this aim, the research formulated two objectives and two research questions were raised to guide the research, while two hypotheses were also formulated and tested at 0.05 level of significance. The design used for the study was ex-post facto research design to determine the possible relationship and effects of the dependent variables. The population of the study consist of three Colleges of Education in Plateau State. A sample of 1200 NCE students results of both microteaching and teaching practice were used as sample for the study. The sampling technique used was stratified random sampling technique. The data for the study was collected using Microteaching Observation Checklist (MOC) and Teaching Practice Assessment Checklist (TPAC) which has been developed by National Commission for Colleges of Education, (NCCE). The validity and reliability of the instrument was sought and based on the judgment of experts, the instrument was found to be valid and reliable with a reliability co-efficient of 0.7. The data collected was analyzed using mean and standard deviation for the research questions and t-test for unrelated samples of hypotheses one and three and analysis of covariance ANCOVA for hypothesis two. Findings from the study revealed that the experiences of microteaching and its effectiveness improved the performance of the pre-service teachers at the teaching practice exercise and the actual teaching profession. It was recommended among others, the need for teachers in curriculum studies to encourage and lay emphasis on the various skills in microteaching: Class control, use of instructional materials, and set induction.