Abstract: This research aims to describe effectiveness of Investigation Based Multi Representation (IBMR) model learning device with contextual approach to improve student problem solving skill in State High School 18 Surabaya in material of Newton’s Law. The learning device is being developed using 4D design with one group pre-test post-test research design. The research data is obtained from result of pre-test and post-test of problem-solving skill, student activities during learning, and student responses after learning. Result of problem-solving skill is then being analyzed using n-gain test and paired t-test. Result of research shows that IBMR learning with contextual approach is effective to improve student problem-solving skill with medium category which is supported by student activities during learning that shows a very good result and student responses after learning is very positive.