To prevent the rockfall disaster, the Rock Shed with energy-absorbing system have been usually used. This study developed a new test method using Newton's Cradle apparatus coupled with contact and non-contact dynamic measuring systems to examine the energy-absorbing efficiency when Expanded Polystyrene (EPS) subjected to rockfall impact force. The contact measuring system was consisted of accelerometer and dynamic load cell, and the non-contact system was established using optical image analysis technique. The test results showed that the measured acceleration and impact force has a good agreement with that from theoretical solution. In addition, the energy-absorbing rate of 67% and 72% with respect to different test specimen size was investigated.