Objective To study a quantitative indicator for measuring the similarity between blood pressure waveforms and its application in the analysis on the simulated blood pressure waveform for pulsatile flow simulation system.Methods Based on the past similarity measurement algorithm and the known feature of blood pressure waveforms, the weighted average algorithm was presented in this paper, which possessed advantages of both global matching and partial matching by integrating the correlation coefficient with the characteristic parameter algorithm, and calculating similarity degrees through overall and partial waveform.Results The weighted average algorithm was proved to be more suitable for the analysis on the blood pressure waveform similarity compared with the angle cosine method, average absolute deviation method, and numeric similarity coefficient method.Conclusions The weighted average algorithm showed excellent ability in calculating the similarity degree between different waveforms, or in comparing the performance with different pulsatile flow simulation systems, and it could be applied to other physiological waveforms with further improvement.