Abstract: Taking the interference between cathodic protection systems of parallel oil and gas pipelines in southwest mountainous area as the research objects, BEASY software was used to simulate and calculate the effects of several factors on the interference between cathodic protection systems of pipelines, and the pipeline interference was alleviated by on-site bridging. The results show that the interference between cathodic protection systems of parallel pipelines gradually decreased with the increase of parallel pipeline spacing. When the damage rate of the coating on the interfered pipeline was large, the negative shift of pipeline potential was obvious. The interference degree between cathodic protection systems of parallel pipelines increased with the increase of soil resistivity, and the potential shift showed a trend of decreasing in boundaries. Bridging could effectively improve the cathodic protection effect of pipelines with poor cathodic protection levels, and reduce the interference degree between parallel pipelines.