Mechanical snubbers have often been used as supports for the piping in nuclear plants, but, recently the elasto-plastic-type piping support devices (named energy absorbers), which are low-cost and maintenance-free, are planned for use instead of snubbers. Under these circumstances, to establish the concept of the piping design method using the elasto-plastic-type piping support devices, device test and vibration test of the piping system supported by elasto-plastic-devices were performed. By the results of these tests, we confirmed the following items: (1) The evaluation formulas for the force-displacement relation and the dissipated energy of devices were established and considered to be reasonable in comparison with the test results. (2) In the case of the piping system investigated, the maximum damping ratio is about 10%.