Disclosed herein is a method for managing customer relationship through multiplex-assigning password of access point. According to an exemplary embodiment of the present invention, a method for managing a customer relationship by a customer management server includes: receiving customer terminal information including customer terminal identification information and customer group identification information within a shop being transmitted by accessing the access points of a plurality of customer terminals; and setting the plurality of accessed customer terminals as the same group in customer groups within the same shop based on the received customer group identification information within a shop and storing the set group in customer information corresponding to the customer terminals included in the group as customer social information.