The Chinese standard Q/SHR001-95 for base stocks is compared with the API specifications. The viscosity-temperature characteristics of base stock required by lube oil in use and market demand on oil quality are analyzed. The quality indicators of base stocks in China and other countries are compared. A new classification of base stocks in response to the requirements of modem lube oil is proposed and the research on new technology to produce premium base stocks meeting API specification is recommended on the basis of current base stock processing technology.