A method, device and system for obtaining a local domain name are provided. A Dynamic Host Configuration Protocol (DHCP) request from a User Equipment (UE) is received, in which the request carries an option for indicating returning a domain name of a local domain where the UE is located; and the domain name of the local domain where the UE is located is obtained according to the DHCP request, and the domain name of the local domain where the UE is located is carried in a DHCP reply message to be returned to the UE. A device and system for obtaining a local domain name are also provided, which solve the problem that a user is incapable of obtaining a local domain name after full authentication, so that a UE can perform fast re-authentication during a handover, thereby reducing a handover delay and improving the user experience.