Abstract: In order to prevent Grapholita delineana and reduce the loss of industrial hemp pests.Two microbial inoculums were applicated in the field experiment with usual dosage and block desighn, the test result in safe, efficient and long-lasting agent against hemp borer. The paper showed that the average control effect of Metarhizium anisopliae preparation and Beauveria bassiana preparation on industrial hemp moth was the best at 47 days and 54 days after spraying after sowing, which were 85.85%-88.89% and 64.71%-64.81%, respectively. The population decline rate of Metarhizium anisopliae was almost flat at 41 days, 47 days and 54 days after spraying, which was 83.72%-88.89%. The population decline rate of Beauveria bassiana was almost flat at 47 days, 54 days and 61 days after spraying, which was 63.16%-64.81%. there was not significant difference between corrected controlling effects of Metarrhizium anisopliae and Beauveria bassiana,which were 43.83%-79.87% and 47.14%-83.84% respectively, while spraying in the fast growing period, which the population decline rate of M.anisopliae and B.bassiana reached the best at 15 days after spraying, which were 82.03% and 86.09%, respectively. There was no significant difference between the two preparations.For continuous cropping industrial hemp cultivation fields, it is recommended to spray Metarhizium anisopliae or Beauveria bassiana preparation to control the hemp borer after sowing. During the rapid growth period, it is recommended to spray microbial insecticides combined with chemical insecticides to rapidly reduce the pest population and prolong the control effect.