Abstract: The field experiment about atmospheric particles were conducted in Tianjin during 1989.The results showed that the particles size distributed is partial state.Most particles ranged in the radius that were less than 2μm. Alkline materials are mainly in the coarse particles and acid materials in the fine particles.The data of the Tianjin with the data of Chongqin and Guiyang cities are compared.The results showed that the contents of sulfur element in particles were about same in Tianjin and Chongqin, Gaiyang, but the alkline elements in particles were more larger in Tianjin than in Chongqin and Guiyang.It is maybe important cause that acid rain appeared is South China but scarely appered in North China.