Abstract: With the increasing number of polymer flooding wells in mature oilfield blocks, the produced fluid contains polymers, resulting in higher viscosity and density than those of water-flooded crude oil. This has led to increased back pressure and frequent blockages in oil gathering pipelines. At present, the on-site solution to pipeline blockages has relied mainly on hot washing trucks. However, this method not only causes production losses, but also requires substantial labor input, leading to poor economic benefits. To address this technical bottleneck, the research conducted targeted experiments simulating the actual fluid working conditions of polymer flooding wells. The experiments focused on testing the fluid viscosity changes and back pressure data in pipelines under different combinations of magnetic field frequencies and heating temperatures. The experimental results showed that when the magnetic field frequency was set at 20 000 Hz and the pipeline heating temperature was controlled at 40 ℃, the crude oil viscosity dropped to the minimum value, with the corresponding pipeline pressure 0.017 MPa. Under this operating condition, the fluid in the pipeline has a low viscosity and good fluidity, fundamentally avoiding the problem of pipeline blockage. It's verified that electromagnetic heating technology can effectively reduce the viscosity of polymer-containing crude oil and significantly reduce the back pressure of oil gathering pipelines. To verify the on-site applicability of the technology typical polymer flooding wells were for field application tests and a comparative analysis with the flushing effect of traditional hot washing trucks was conducted. The field application results indicate that the electromagnetic heating technology does not require the interruption of oil production operations during implementation, and it has a stable control effect on pipeline back pressure, further confirming its on-site promotion value. Electromagnetic heating technology provides an efficient and economical new approach to solving the problems of high back pressure and frequent blockages in oil gathering pipelines of polymer flooding wells, which provides effective support for development of polymer flooding in mature blocks.