Reciprocating compressors require gas volume regulation during partial load operation, and the gas pulsations in the pipeline exhibit different patterns under various regulation conditions. If the gas pulsation intensifies, it could threaten operational safety. This paper focuses on four gas volume regulation methods (M1–M4), establishing a coupled working process and gas pulsation model for the cylinders, and analyzing their pulsation characteristics through experimental verification. The results show that: variable rotational speed regulation (M2) can suppress pulsation by increasing the speed (200~300 r/min); supplementary clearance volume regulation (M3) shows pulsation peaks at gas loads between 70 and 90%; full stroke suction valve unloading regulation (M4) results in a sharp frequency change due to stepwise regulation (at 50% gas load, the dominant frequency is 5 Hz); stepless regulation methods (M1 and M3) maintain stable dominant frequency (10 Hz) at 50% gas load, reducing pulsation amplitude by 15–20%, offering the best overall performance.