The work aims to conclude the internal corrosion law and residual service life of pipelines by means of the simulation of and the experimental study on the internal corrosion of oil-gas pipelines containing CO2. Based on the actual working conditions of some pipe in the western area of the Bohai Sea, OLGA software and De Waard95 model were selected to simulate and analyze the factors influencing CO2 corrosion rate. Weight loss experiment was adopted to research the effect of temperature and partial pressure of CO2 on the corrosion rate of X52 pipeline steel. The residual service life of corroded pipelines was predicted based on the simulation data. The simulation results showed that the temperature, pressure, liquid holdup, flow pattern and pH value along the pipelines had great influence on CO2 corrosion rate. Experiment showed that: with the increase in temperature, CO2 corrosion rate increased firstly and then decreased. The maximum corrosion rate reached 0.22 mm/a at 333 K. Corrosion rate increased with the increase in CO2 partial pressure, and the maximum value was 0.24 mm/a. With the change in piping elevation and mileage, different factors have different degrees of impact on CO2 corrosion. The corrosion rate of pipelines inlet section is the largest. The results of simulation and experiment provide certain reference value for internal corrosion protection and prediction of residual service life of the pipelines.