Since its start in 1995, Japanese New Car Assessment Program (JNCAP) has conducted full-wrap frontal collision test (since 1995), side collision test (since 1999) and offset frontal collision test (since 2000), aiming for enhancing collision safety performance for drivers and front seat passengers. Safety performance of rear seat passengers had long been outside the scope of evaluation in JNCAP;​ however, as it became mandatory in 2008 for rear seat occupants to wear a seat belt, and the seat belt wearing rate has begun to improve, the safety assessment for rear seat occupants with seat belts has increasing its significance. Under the above circumstances, JNCAP has amended the protocol of offset frontal crash test and introduced occupant protection methods for rear seat passengers in 2009. We adopted Hybrid III AF05 (female dummy) in rear seat instead of AM50 (male dummy) in front passenger seat, considering that women are more likely to become the rear seat occupant. And JNCAP developed its own rear seat dummy evaluation method referring to the FMVSS208[1] and new US-NCAP[2]. JNCAP has publicized this unique test result of 11 models so far. As this is a relatively new method, we have experienced some difficulties in evaluating safety performance of rear seat occupants accurately. In this paper, we will provide the latest results and findings during our experience in the rear occupant protection JNCAP tests.