Abstract: We studied the virulence of Metarhizium anisopliae and predation by Carabus smaragdinus against Locusta migratoria manilensis and their interaction effects on the pest population. M. anisopliae was harmless to C. smaragdinus. When treated with releasing C. smaragdinus combined with spray of M. anisopliae, and releasing M. anisopliae-inoculated C. smaragdinus, the predation rate were 64.19% and 61.23%; infection ratewere 70.85% and 75.34%; the corrected mortality rate were 83.3%, and 100%, respectively, which were higher than those achieved with C. smaragdinus or M. anisopliae alone. The results indicate that control of L. migratoria by dissemination of M. anisopliae using C. smaragdinus as the vector is a potential choice.