Resumo. Emamectin Benzoate was registered recently in Brazil to control Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae) in soybean. We studied the baseline susceptibility of Mato Grosso populations of C. includes to support Insect Resistance Management programs by standard feeding assays on insecticide-surface of artificial diet. Variation in susceptibility between populations was low. The LC50 values from 11 populations varied between 0.015 a 0.065 µg i.a. cm-2. Based on our results, we propose the discriminant concentration of 2.867 µg i.a. cm-2 of emamectin benzoate to monitor insecticide resistance in C. includes.