Abstract: The schemes in numerical model of study the evolution of size-dist ribution spectrum of hydrometeoro particles can be divide into two types:parameterization method and category method,and an example of category SGBH model is given.Some questions of itself or in application of paramet erization methods are discussed.The results of discussion indicate that the category method have to use in the treatments for the production of future generation particles by autoconversion,artificial seeding effects and the processes concerned obviously the move regime of particles.