Abstract: Important provisions of ultrasonic test provided by RCCM code, ASME BPVC code and GB/T 2970 code have been introduced and compared. The discussion was based on different industry code complying with the different nuclear power plant model design regulation. Essential variables of ultrasonic examination were discussed through comparison and andysis, and at the same time, the engineering feedback was also considered. The main suggestions are made. It is necessary to consider attenuation area. The criteria are also dependant on the different areas. It may provide reference for using properly standards in the process of nuclear plate design and procurement.