Abstract: Carborundum tube simulation method was employed to study the changes of soil pH, major available nutrients and organic matters after application of organic materials in tobacco fields of puple soil in Nanxiong, Guangdong Province. Results showed that application of rice straw, peanut cake fertilizer, pig manure and bio-organic fertilizer could enhance the contents of soil available nutrients in 30-60 days after transplanting, with the maintenance of soil fertility and the improving of organic matters quality. The peanut cake fertilizer could most remarkably improve the content of available nitrogen, followed by bio-organic fertilizer, and the nitrogen level in both treatments declined at the 60th day after transplanting. Bio-organic fertilizer exhibited the optimum maintence of soil fertility and improving of organic matters quality.