Abstract: The paper analyzes the quality specifications and performances of external coatings for pipeline, and summarizes the recent application of coatings home and abroad. In recent years, the coal-tar primer and double or triple layers' polyethylene structure used as the external coatings have been widely used in the most of pipelines in China. By means of analyzing and comparing the performances, applicable scope and pros and cons of several coatings, the selection principle of coatings is presented.