Abstract: Take Tieling–Dalian Crude Oil Pipeline as a research object, through statistics and analysis of actual paraffin precipitation conditions of fieldpipeline transformed by fire work and based on changes of transportation process and medium in recent 10 years, the distribution law ofparaffin sediments in the pipeline is determined preliminarily. Heat exchange between the crude oil in the pipeline and ambient environmentis an important factor to decide thickness, distribution and intensity of pipeline paraffin precipitation. Differences in oil temperature, environment, insulation effect, etc. of the pipeline are an important reason for uneven paraffin precipitation distribution in the pipeline.Random drift and accumulation of shedding paraffin blocks enhance irregularity of pipeline paraffin sediment distribution pattern. Seriousparaffin blocking in local pipe sections causes a significant increase of average paraffin thickness. For the pipe section subject to seriousparaffin precipitation, pipe cutting observations, dense opening for pressure measurement and other traditional means are still needed todetermine actual paraffin precipitation conditions of the pipeline, and roughly, current paraffin sediment amount within the pipeline can becalculated.