The objective of this study was a preliminary study of the responses of dummies seated in the 2nd row seat of passenger vehicles in frontal crashes using a sled system. Q6, Hybrid III 5th female, Hybrid III 5th pregnant female, and Hybrid III 50th male ATD were used in the tests. 8-tests were carried out according to a draft protocol for the 2nd row seat evaluation program. The vehicle type was a sedan and SUV’s. The cut-body or jig was used to simulate the ATD in the 2nd row seat/belts of a passenger vehicle. The frontal crash pulse in sled tests was an average acceleration of about 30 vehicle acceleration pulses tested according the KNCAP FFRB test. ATD seating positions were set using the H-point machine. Injury criteria were considered among the HIC15, upper neck tension force, chest deflection. The HIC15 ranged from 350 to 800 for both a Hybrid III 5th female and a pregnant female. The upper neck tension forces of a 5th female dummy and a 5th pregnant female dummy were also higher than that in FMVSS 208. The kinematics was influenced by the seat and seatbelt characteristics. The sled test results were compared with those of the same vehicle KNCAP FFRB test results. The possibility of fatal injury of Hybrid III 5 th female and 50 th male ATD in the rear seat could have much higher than in the front seat, especially case of the chest deflection. In addition, the further consideration should be given regarding Y- axis in the regulation at the seat belt anchorage point.