Since Lipsky started the theory of Street-level Bureaucracy in 1980s,street-level bureaucrats attract the attention of the experts and scholars domestic and abroad.After 30 years of development,the theory of Street-level Bureaucracy has been integrated and developed continually.Discretion is the core of the theory of Street-level Bureaucracy.Therefore the experts and scholars domestic and abroad have a heated discussion about the discretion of street-level bureaucrats.Throughout all the discussions,they generally can be divided into two types：one is that street-level bureaucrats should possess legitimate discretion to a certain extent,the other is discretion of street-level bureaucrats should be weakened and even eliminated.