Abstract: In order to promote the green prevention and control technology in pest control through insects,and reduce the use of chemical pesticide in rice field,the single-factor experiment was adopted to arrange the treatments with 3species of Trichogramma,including Trichogramma dendrolimi,Trichogramma japonicum,as well as the mixed Trichogramma with Trichogramma dendrolimi and Trichogramma japonicum（3:1）,and several related indices such as parasitism rate,effects of prevention and control as well as output were investigated by taking Trichogrammabeing not released as the blank control（CK）.The results showed that the parasitism rate,correction parasitism rate,effects of prevention and control,yield and recovered yield loss of the treatment with Trichogramma japonicum were respectively 72.72%,70.45%,64.1%,737.93kg·（667m~2）^-1and 4.86%,which were all in the highest level,and had no significant difference with the treatment of mixed Trichogramma.It is concluded that Trichogramma japonicumis the dominant species parasitic on the eggs of rice stem borer.The application of Trichogramma japonicum or mixed Trichogramma with Trichogramma dendrolimi and Trichogramma japonicum（3:1）to control rice stem borer can achieve ideal control effect.