Box tree moth, Cydalima perspectalis is native to East Asia where it occurs on Buxus trees. Its natu-ral distribution includes China, Japan, Korea and India, and it was accidentally introduced into Europe, Middle East, North America and north Africa through the trade in Buxus spp., where it can cause considerable damage. In the native range of C. perspectalis, three tachinids (Diptera, Tachinidae) are known to parasitize larvae of C. perspectalis, including Exorista sp., Pseudoperichaeta nigrolineata (Walker 1853) and Compsilura concinnata (Meigen 1824). Data on tachinid parasitoids parasitizing C. perspectalis on the European continent include only P. nigrolineata. Field collection of mature larvae and pupae of C. perspectalis during July 2020 in four locations in Split – Dalmatia County in Croatia resulted in collection of live tachinid larvae that were reared to adults. The tachinid specimens were identified at the Natural History Museum, London, UK, as Nemorilla flo-ralis (Fallén, 1810) (Diptera, Tachinidae). Conservatively, 1.2 – 2.4 % parasitism rate was achieved. This is the first world record of N. floralis parasitism on C. perspectalis larvae, which can be added as a potential tool for C. perspectalis biological control.