The overall aim of this study is to search whether teaching geometry with Cabri Geometry Plus II software have effects on 7th grade students' learning transformation geometry in mathematics. In this context, the researcher has used a pre-test and post-test research design with a control group. The research sample consisted of 135 students in total with random selection method. In the experimental group consisting of 66 students, teaching process by using Cabri Geometry Plus II software has been explained in a six-hour lesson period. In the control group consisting of 69 students, the transformation geometry has been also explained in a six-hour lesson period by making use of traditional teaching method. 20 questions of Mathematics Achievement Test have been asked to collect the research data. The data obtained from Mathematics Achievement Test has been analyzed through dependent and independent testing with SPSS Program. As a result of the data analysis it has been inferred that there have been improvements in the academic achievement of the students in the experimental and control groups, but the academic achievement of the students in the experimental group have been found to be higher when compared to the students in the control group. In other words it is concluded that between the students in the experimental and control groups have significantly different levels of achievement. According to this result, using dynamic geometry software Cabri program while teaching transformation geometry has been found to increase success levels of the students in the experimental group.