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In this study, we investigated parasitism rates and host-parasite interactions between the brood parasitic Asian koel (Eudynamys scolopacea) and its hosts in an area in Bangladesh. Three species were found to be utilized as hosts: long-tailed shrikes (Lanius schach), common mynas (Acridotheres tristis) and house crows (Corms splendens) with parasitism rates of 35.7, 31.2 and 10.8%, respectively. This is the first time the long-tailed shrike is reported as a host for the Asian koel. Cuckoo reproduction was successful in a relatively high proportion of host nests (25-46.5% of parasitized nests produced at least one cuckoo fledgling), with no significant differences in cuckoo breeding success among host species. Cuckoo egg mimicry was good in house crows as compared with the two other host species, supporting previous observations that the house crow is a major host. Even though the cuckoo eggs were highly non-mimetic with long-tailed shrike and common myna eggs, none were ejected. However, mynas were more likely to desert parasitized nests than non-parasitized ones. More than one cuckoo egg per nest was commonly found and all cuckoo eggs were accepted by all hosts. All three host species suffered costs of parasitism in terms of reduced breeding success, as the proportion of own young produced was significantly lower in parasitized than in non-parasitized nests. We discuss why these hosts are such poor rejecters of cuckoo eggs despite the high costs of parasitism.