The damage mechanism of land-based laser air defense weapon was described from software failure and hardware damage,combining the characteristics of air combat under information conditions,the construction of weapon system was set,six characteristics:instantaneity,flexibility,elusive,continuity,stability,controllability of land-based laser air defense weapon were summarized.Kill zone of weapon system was delimited based on boundary threshold,six kinds of targets of land-based laser air defense weapon were summed up,focuing on the characteristics of targets.