In order to determine the colonization efficiency of Beauveria bassiana and Metarhizium anisopliae in corn and the affection of gongzhulingmycin, three kinds of biological agents were inoculated together in corn with corn straw granule as a kind of microorganism-carrier. Colonization rate of B. bassiana and M. anisopliae were detected.The result shows that colonization rate of B. bassiana and M. anisopliae in treatment of B. bassiana with M. anisopliae was 47.5% and 78% respectively, significantly higher than other treatments and the control. Colonization rate of B. bassiana and M. anisopliae in treatment of three kinds of microbial agents were 25% and 50% respectively,lower than other treatments and the control. Our results indicated that combination of B. bassiana with M. anisopliae could increase the colonization efficiency each other. Gongzhulingmycin could inhibit the synergistic action of B.bassiana and M. anisopliae, but there is no significant effect on colonization efficiency of B. bassiana or M. anisopliae.