Addressing the current issues of low accuracy in calculation methods for gas pulsation in high‑pressure pipelines and insufficient research on gas pulsation in hydrogen storage and transportation compressor pipelines，a study on the calculation and testing of gas pulsation in a 90 MPa hydrogen diaphragm compressor pipeline was conducted.An algorithm for 1D unsteady flow in pipelines based on real gas properties was proposed to solve the physical quantities of pulsating gas flow at various points in the pipeline in the time domain.Experimental tests for gas pulsation were performed on the second‑stage exhaust pipeline system of a hydrogen diaphragm compressor under three pressure conditions：90，63.5，46 MPa，with analysis conducted using a self‑developed numerical program.The results show that the calculated pressure pulsation at the measurement points agrees well with the measured data，with larger amplitudes for low‑order harmonics below 100 Hz.The pressure pulsation level is highest at the cylinder outlet （peak‑to‑peak value of 13.4 MPa） and decreases to a lower level downstream at the buffer tank （peak‑to‑peak value of 2.5 MPa）.The variation of pressure pulsation with rotational speed differs across pipeline locations.The changes in pressure pulsation at the cylinder outlet and measurement points exceed 2% of the local average pressure，while the variation with rotational speed is smaller in the pipeline sections near the buffer tank.The buffer tank reduces the maximum pressure pulsation in the pipeline by more than 25%.From the perspective of suppressing maximum pressure pulsation，there exists an optimal value for the buffer tank's inner diameter.The research findings can provide technical support for the design and modification of pipelines in high‑pressure hydrogen storage and transportation compressors.