A method for identifying a user device includes: receiving uplink messages sent at least twice by the same user device; on the basis of the uplink messages sent at least twice, determining remote radio unit (RRU) positional information of each RRU that receives an uplink message; judging whether a proportion of a number of different pieces of the RRU positional information among at least two pieces of the RRU positional information to a total number of the at least two pieces of the RRU positional information reaches a preset proportion threshold; when the ratio does not reach the preset ratio threshold, determining that the user device is a common user device; and when the ratio reaches the preset ratio threshold, determining that the user device is a fast-moving user device.