The invention discloses anti-conflict mobile terminal IP address allocation relay equipment and method. The method comprises the following steps: receiving a request message which is sent by a user terminal and used for requesting allocation of an IP address by the relay equipment, determining position information of a client according to the address request message, acquiring a corresponding relationship between the position information and the IP address, determining the IP address corresponding to the position information of the client according to the corresponding relationship, and detecting whether an IP address allocation conflict exists or not according to user online information; and if so, marking a current IP as allocated, reselecting one of remaining unallocated IP addresses randomly, and transmitting the randomly-reselected address to the client. The relay equipment provided by the invention is designed with an address buffer storage, so that an IP address can be reallocated to equipment which is already allocated with an IP address in a short time. Through the technical scheme provided by the invention, the problem of IP address allocation conflict in a DHCP (Dynamic Host Configuration Protocol) server can be solved; the allocation efficiency is increased; and the high efficiency and reliability of an underground communication system are improved.