Abstract: The vertical physicochemical properties and fungi, bacteria, actinomycetes number under various tobacco planting soil types in Kunming tobacco areas were investigated to explore their relationship with tillage depth. The results showed that contents of organic matter, available N, available K, and number of fungi, bacteria, actinomycetes had a significantly or highly significantly negative correlation with profile depth of purple soil, paddy soil and red soil. The contents of exchangeable Ca and exchangeable Mg of paddy soil had highly significant negative correlation with profile depth, purple soil and red soil only showed negative correlation. Nutrient contents and microbial numbers in all of the three tobacco planting soils showed characteristics of strong surface accumulation, decreasing from top to bottom. Considering these nutrient and microbial number change, it is suggest that appropriate tillage depth is 20 cm purple soil, 20-30 cm for paddy soil and red soil. In production practice, nutrient contents will decline largely if the plough layer is too deep (> 30 cm). Therefore, additional fertilizers should be applied.