Abstract: Based on the investigations on the practices of import/export of seamless steel tubular goods both at home and abroad, it is concluded that the categorization of H.S. Code for seamless steel tubular goods currently adopted by Chinese Customs is too general, and is no longer suitable for guiding relevant import/export activities particularly in the post WTO era of China. The necessity and effectiveness of sub-categorization of H.S. Code for seamless steel tubular goods are discussed, and the method for possible sub-categorization in line with China’s circumstances is proposed with reference to the similar H.S. Codes currently employed by U.S. Customs and Canadian Customs.