Abstract: As an important supplement to pipeline integrity assessment, comparison of data from two or more inline inspections can help to fully search useful information contained in them to enhance utilization rate of the data. Combined with field applications, this paper presents the matching method, comparsion method of data from 2 inspections and their differences, and the way to use data comparison results to identify and solve existing problems in integrity assessment. The research results show that, through comparison of data from two or more inspections, root causes for various defects can be analyzed, and active corrosion can be clarified in pipelines, accordingly, corrosion rates can be calculated scientifically and uncertainties can be minimized in pipeline integrity assessment.