Abstract: Genetic algorithm (GA)is a random search method which is suitable for the optimum of model parameters because of its global optimum.Optimal contribution rates of atmospheric particulates of each pollution source were calculated by using GA to optimize the parameters in CMB equation sets of sources apportionment of atmospheric particulates.Results of sources apportionment of atmospheric particulates in Chengdu using GA tallied with that of sources apportionment of other methods.It is shown that GA is simple,precise and practical for sources apportionment of atmospheric particulates by the theoretical analysis and practical application.