Abstract: According to the dynamic features of NGSO MSS networks,this paper puts forward a hybrid channel assignment scheme.In the scheme,fixed channels are allocated to cells for exclusive use as nominal channels and reallocated after periodic time in terms of time-variant traffic distribution using ununiform compact pattern allocation algorithm. Available algorithm is used to assign dynamic channels.Computer simulation results show that the HCA scheme has better performance compared with FCA scheme and can effectively reduce handover failure and call disruption rates on channel updating times,thus greatly improve network traffic-carrying capacity.