Teaching Practice is a required course for all students in education programs, divided into two sections. The first, is intended as the process of creating Syllabus, teaching plans, instructional medias and supporting material for "peer teaching" practice. The second, is intended to assign students to do classroom teaching. "Lesson Study" (LS) has been integrated in the State University Of Malang for a while. It was decided to integrate it in teaching practice of all students after the benefit of Lesson Study was recognized. This study tries to describe the integration of LS in teaching practice for students teachers; the implementation of Lesson Study in the teaching practice of the Social Studies student teachers; the benefits of the implementation of LS in the teaching practice; and the constrains and the supporting factors in integrating teaching practice for Social Studies students teachers. In this qualitative study, the researcher analyzes documents, conducts observations, gives open ended questions interviews and leads focus group discussions. Lesson Study has strengthened the process of teaching practice and promoted the competency of Social Studies student teachers. Classroom teachers and Social studies student teachers recognize the importance of continuing teaching-learning improvement that can be done by applying Lesson Study.