Abstract: To clarify the effects of organic fertilizer type on the reduction of nitrogen leaching loss from tobacco soil in Erhai tobacco growing area of Yunnan Province and the relationship between the application rate of organic fertilizers and nitrogen leaching loss from tobacco growing soil, indoor soil column simulation experiments were conducted using mixed organic fertilizers, biochar fertilizers, and sesame cake fertilizers as study materials. The results showed that: 1)At the same nitrogen application rate with 30% chemical fertilizers replaced by organic nitrogen fertilizers, the leaching amounts of nitrate nitrogen and ammonium nitrogen and the ¹⁵Nδ value under different organic fertilizer treatments averagely decreased by 29.56%, 7.18% and 37.83%, respectively. 2)The leaching amounts of nitrate nitrogen and ammonium nitrogen and the ¹⁵Nδ value decreased by 32.59%, 9.95% and 41.17% in the biochar fertilizer treatment, respectively. The decreases were greater than those of the mixed organic fertilizer and the sesame cake fertilizer treatments. 3)As the application rate of the organic nitrogen fertilizers increased, the leaching loss of nitrogen from tobacco growing soil showed a downward trend. The leaching loss of nitrate nitrogen and ammonium nitrogen in the 100% organic fertilizer treatment decreased by 51.14% and 22.88%, respectively. The biochar fertilizers had a good effect on the reduction of nitrogen leaching loss from tobacco growing soil in Erhai tobacco growing area. There was a linear negative correlation between the application rate of the organic fertilizers and nitrogen leaching loss from tobacco growing soil, and increasing the application rate of organic nitrogen fertilizers contributes to the risk reduction of nitrogen leaching pollution from tobacco growing soil in Erhai tobacco area.