The purpose of this study is to investigate the effects of cooperative learning supported with reflective materials on Turkish teacher canditades' self-regulated learning. Pre-test and post-test experimental design with control group was utilized. Data of the research were collected through the Turkish version of the Motivated Strategies for Learning Questionnaire. Eighty Turkish teacher candidates (38 girls and 42 boys) participated in this research. The reflection materials were provided for the experimental group only. Both groups were taught by using the principles of cooperative learning. The research has discerned that there is a difference between experimental and control groups on Self-Efficacy for Learning and Performance. However, it has been found that cooperative learning supported with reflection materials affects self-regulated learning more positively.