Abstract: In order to solve the problem of interference and resource management in ultra-dense networks (UDN), a resource allocation algorithm based on intra-clustering grouping is proposed. The algorithm is divided into two modules: the first module is splitting FUE (Femtocell User Equipment) group on the basis of the clustering of FBS (Femtocell Base Station); the second module is firstly satisfying the precondition of resource allocation of the optimal SINR for FUE group, then to allocate resources for FUE according to the priority in same. The simulation results show that the proposed algorithm can reduce the interference of the same FUE group. Simulation shows that the algorithm effectively reduce the co-tier interference in UDN, improves the throughput and spectrum efficiency of the FUE, promotes overall system performance and satisfies the requirement of FUE at the same time.