This study aims to develop a realistic mathematics learning model using cooperative strategy. This study applies research and development approach conducted at Junior High School "Laboratorium," State University of Malang. The implementation of this model is conducted through five stages: 1) previous study phase; 2) model planning phase; 3) model implementation phase; 4) practicality assessment phase, and 5) model effectiveness phase. The result of this study shows that the model that has been developed can be used by teachers through focusing the attention to express students' ideas; besides, it is also used as a model to improve the quality of mathematics learning through the improvement of teacher professionalism.