This research aims to determine the effectiveness of cooperative groups, organized according to learning styles, on students' physics success. The research was designed according to non-equivalent control group design. In the experimental group, the students were assigned into cooperative groups heterogeneously according to their learning styles and in the control group the students were assigned into cooperative groups according to their academic success. At the end of the research, it was seen that the students in the experimental group were more successful than the students in the control group. In addition, it was determined that there was no significant difference on the experimental group students' success according to their learning styles, but that the auditory students were more successful than the visual and kinesthetic ones in the control group.