Abstract: Boron is important element of growth of tobacco. Lager area of Yellow Soils area in Chongqing is planting tobacco, while the content of boron was low, which was one of important limiting factor of crop’s growth in this area. Author was menstruated content of boron and researched the status of lack of Boron and researched relativity of its Influencing facto, the results showed that the average content of available boron in the yellow soil was 0.39±0.27 mg/kg, 80 percent of its was under 0.5mg/kg which was lack for boron and 17.44 percent of its was under 0.2mg/kg which was especially lack for boron; The distribute frequencies of available boron contents of yellow soils in Chongqing was dispersedly, its range of 0.07mg/kg to 1.99mg/kg. The diversity of different zoology area was distinct. The result of pertinence analyses showed that available boron contents had correlativity with the pH(r=0.181** n=281) and CEC（r=0.124** n=281) and It had correlativity with Organic matte When the content of organic matte is high; in addition, soil granule、clime was the Influencing factor of availability of boron in Yellow Soils in Chongqing.