A system and a method for measuring and configuring miss-configured 2G neighbors in a 3G network. The system comprises a user equipment, an operation and maintenance center, a radio network controller and a data register, wherein the operation and maintenance center further comprises a measurement information unit and a configuration unit, and the radio network controller further comprises a measurement control unit. The method comprises the steps of: setting parameters and measuring 2G neighbors in a 3G cell according to the parameters; generating a to-be-measured 2G neighbor list and delivering the to-be-measured 2G neighbor list to the user equipment for measuring; receiving report of measurement information of the 2G neighbors from the user equipment, and if the reported measurement information of one of the to-be-measured 2G neighbors meets condition of miss-configuration, adding the one to the miss-configured 2G neighbor list.