In cellular mobile communication network,for ensuring greatest compact assignment and reducing the blocking rate and dropping probability of calls,an improved hybrid immune algorithm was presented and applied to dynamic channel allocation.In the algorithm an adaptive population initialization,a crossover and reorganization operator,an improved selection mutation technique and an improved vaccination method were adopted.When traffic increases by 80%,the blocking rate,the dropping probability and the average number of convergence generation of the algorithm are respectively 3.48%,1.91% and 9.98 times.The simulation results show that the modified algorithm can improve the convergence rating and reduce the number of running generation required for convergence,significantly reduce the blocking rate and dropping probability of calls,and has more traffic carrying capacity.