Abstract: Eucommia ulmoides forest land was taken as an example,the effects of different fertilization treatments on the growth of Bletilla striata under forest cultivation were studied by using incomplete fertilization design. The results showed that (1) the fertilizer could promote the growth of Bletilla striata under forest cultivation.The seedlings grew the best with the height of 13.67 cm and the diameter of 0.44 cm when nitrogen phosphorus and potassium (N:P₂O₅:K₂O) fertilizer was 30 kg per 0.067 hectare and fertilization on plant height, ground diameter growth showed significant difference (P<0.01); (2) The effects of fertilization were studied on the growth of Bletilla striata tubers, with the increase of fertilization amount, the tuber length, tuber width, tuber number and tuber weight of Bletilla striata increased gradually; When the nitrogen phosphorus and potassium (N:P₂O₅:K₂O) fertilizer was 30 kg per 0.067 hectare, the tuber grew the best, with its length 40.67% higher than that of the control (CK), width 91.27% higher tuber number 79.85% higher, tuber weight 298.90% higher and the highest yield of Bletilla striata; Fertilization on tuber length, width, number and tuber weight growth showed significant difference (P<0.01); (3) It was suggested that organic fertilizer should be applied before planting in Bletilla striata under forest cultivation, and nitrogen fertilizer should be applied in the fast growing stage. Nitrogen, phosphorus and potassium compound fertilizer should be applied in the flowering and tuber swelling stages to promote the growth and development of Bletilla striata tubers.