Abstract: Taking a reciprocating compressor unit of an offshore platform as an example, the vibration response of the reciprocating compressor skid under different constraint boundary conditions is compared and analyzed by ANSYS software. The analysis results show that the vibration analysis of offshore platform component legs are used as the boundary reference and the less deviation of vibration analysis results when the column of offshore platform is taken as the boundary, the amount of calculation is small. It can provide references for the selection of vibration analysis boundary of reciprocating compressor skid on offshore platform.