Abstract: A nano-copper-based composite anti-friction coating is prepared by means of mixing the highlyconcentrated nano-copper suspension liquid with the PTFE particles at an appropriate proportion,and using a special acrylic resin as the binder.The composite anti-friction coating is applied to the N80S,P110S and TP95TS thread connections for the anti-corrosion tubing and casing,and subjected to the mill full-scale makeup/breakout test.The test result shows that after breakout,no remarkable sign of galling or scratch of the thread surface is found,and that due to treatment with the said coating,the anti-galling performance of the thread connection can be significantly improved,and effect is as good as that by the copper-plating process..