Mating behavior of Microplitis croceipes (Cresson), a larval endoparasitoid of Heliothis spp., is described. Sensory events involving antennation and antennal dragging and an excitatory phase characterized by wing fanning were exhibited by males. No overt sexual behavior was seen in females. An understanding of this mating behavior may aid in developing a field monitoring technique for M. croceipes.