Exorista larvarum is a dipteran polyphagous larval endoparasitoid particularly known as antagonist of Lepidoptera. Exorista larvarum is a good biocontrol candidate against forest lepidopterous defoliators. This parasitoid has positive features, among which, it can be efficiently reared in vivo and in vitro. In the laboratory, box tree moth larvae were accepted by E. larvarum females. A lower number of eggs were laid on C. perspectalis than on G. mellonella, but the difference between the two moth species was not significant, although a quite long 3 hours exposure time was necessary for oviposition. We can speculate that, although not the preferred host, C. perspectalis may be accepted by E. larvarum also in nature. The overall results suggest that the mortality of C. perspectalis and G. mellonella larvae due to the partial development of E. larvarum may be useful to regulate the populations of this invasive pest in a context of conservative biological control.