The purpose of this study is to examine the effects of micro-teaching practices with the VuStat program on the techno-pedagogical content knowledge of mathematics teacher candidates. Participants of the study consisted of ten mathematics teacher candidates who continued to fourth grade. Teacher candidates were informed the features and use of the VuStat program through sample tasks over 10 lesson hours (two weeks). Teacher candidates' first presentations were recorded and their both presentations were assessed. A ten-item observation form was used in the evaluation of the presentations. The assessment forms were examined taking into account the positive and negative comments. The results have showed that the positive responses about all the prospective teachers showed an increase compared to the first stage. It was seen that the positive response rate increased from 58.6% to 87.3%. In addition, teacher candidates think that technological constraints exist in stage1, while their views on technology in stage2 showed a positive development.