Abstract: The flow characteristics of Coal-Water Slurry (CWS) and the movement of coal powder in the pipeline transportation of CWS are analysed. Then, the calculation method of CWS pipe wearing has been got by analysing the rub process of coal powder with inner surface of pipe. It has been proved by the calculation results that the pipe wearing is very slight in proof of the feisibility of long distance pipeline transportation of CWS. Detailed measures are also analysed to reduce pipe wearing of CWS.