Abstract: In order to improve soil quality 、the quality of tobacco and inquire into tobacco soil rhizosphere microbial effecting on straw field.So we do this test to compare the straw field with without straw field.[Method]Using the selective medium,a straw field and the rice field soil for the Tobacco targets,the without straw soil as a control tobacco,the tobacco rhizosphere microbial（mainly bacteria,fungi,actinomycetes） were isolated and measured The results show that the straw can significantly increase the tobacco planting soil rhizosphere microbial,s quantity.As the different types of straw,the rhizosphere microbial,s number is different.Overall,the number of the straw field Tobacco soil rhizosphere bacteria and actinomycetes is largest,and the number of the rice field Tobacco soil rhizosphere bacteria and actinomycetes is less than that,and the blank control group Tobacco soil rhizosphere bacteria and actinomycetes is the least.The number of the blank control group of fungi is the largest,followed by the straw field,the rice field is the least.The rhizosphere of the nitrogen-fixing bacteria,bacterial phosphorus and the potassium separating from the different straw soil mainly belong to Gram-negative bacilli bacteria and belong to a 10 separately.The different conditions of the straw field can effect the three rhizosphere bacteria,s type and quantity.Because of the three soil microbial ratio is a measure of the soil,s fertility.Using the straw field can increase the number of rhizosphere bacteria and actinomycetes and improve the soil,s fertility.