n response to problems such as direction-reversing impact, big noises (90～106 dB(A)) and unstable direction reversion in the hydraulic system during the reciprocating compression of natural gas with L-type hydraulic piston CNG secondary refueling station compressors,the dynamic performance parameters of the hydraulic system were obtained through the combination of modeling simulation and prototype testing.Deep research was conducted regarding characteristic parameters affecting the system’s dynamic performance.Optimization and improvement measures for the hydraulic system were advanced.The design and development of the improved hydraulic system were finished and then relevant experiments were carried out as well as dynamic testing to the improved prototype.The results show: the improved hydraulic system of L-typed hydraulic piston compressors has obviously weakened direction-reversing impact, with work noises of not higher than 90 dB and oil temperature increase of not higher than 55 ℃, and the work performance of whole machines has been improved.