A hierarchy model of multiple manager nodes based on DHT was proposed to solve the single-point problem and to improve the lookup efficiency of traditional hierarchical DHT, and then three lookup algorithms, i.e. the shortest path selection algorithm(SPSA), the minimum intra-group traffic based on hot potato algorithm(MIT_HP) and the load balancing with gateway selection algorithm(LBGS), were proposed. Simulation experiments were carried out to analyze lookup efficiency, intra-group traffic and load balance of the three algorithms. The simulation results show that the MIT_HP algorithm has the maximal lookup efficiency but has the worst load balance, the LBGS has the best load balance but has the worst lookup efficiency, and the performance of SPSA is between MIT_HP and LBGS. In addition, the paper presents performance comparison between MIT_HP and SPSA with random lookup algorithm which adopted by traditional hierarchical DHT.