Chemical signals used by parasitoids to find hosts often originate from the host, its habitat, or both, providing critical cues for locating hosts that are often cryptic or highly dispersed. Melittobia Westwood are gregarious ectoparasitoids, which primarily attack Trypoxylon politum Say prepupae. How Melittobia locates its host is unknown, but it may involve host-related chemical signals. Therefore, this study focused on whether host location by Melittobia digitata Dahms is mediated by olfactory stimuli. In a small arena, which contained a choice of potential hosts [T. politum prepupa, Megachile rotundata (F.) prepupa, or Sarcophaga bullata (Parker) puparium], empty host pupal cases, or nest mud—all of which were visually and physically isolated from the parasitoid—Mel. digitata successfully located host patches and spent significantly more time on those than on control (blank and dummy) patches. Results suggest that Mel. digitata females may be arrested by host-related chemicals.