Flies were collected using putrefied baits once a week, a total of 39 times in Mt. Palgong, Taegu, Korea from Feb. 1, to Dec. 5, 1985. The number of flies collected was 33,874, with sex ratio (male/female${ imes}$100) of 38 and the fauna of the fly was found to be 37 species consisting of 10 Calliphoridae, 13 Sarcophagidae, 12 Muscidae and 2 other species. The species Musina assimilis, M. pasuorum, Parasarcophaga shiritakaensis, Graphomyia maculata, Blaesoxipha katoi and Polietes koreicus were collected for the first time by the trap. Especially Polietes koreicus, whose type-locality is Mt. Gumo, was also collected in Mt. Palgong. The nine predominant species, Lucilia caesar, Calliphora lata, Hydrotaea dentipes, Chrysomyia pinguis. Lucilia ampullacea, Muscina angustifrons, Aldrichina grahami, Ophyra leucostoma and Boettcherisca peregrina, constituted 95% of the total collection, among which Lucilia caesar, Calliphora lata and Hydrotaea dentipes contributed 65% of the total. The numbers of the predominant species which collectively occupied more than 90% of the total collection were 8 species in Trap 1,7 in Trap 2 and 6 in Trap 3. This result indicates that the higher the altitude at which the traps were placed, the more monotonous the species composition. The number of fly individuals collected in the trap placed at the higher altitude was larger than that at the lower altitude. Musca domestica and Phaenicia sericata are predominant in human residental area; the former was not collected at all, the latter was found 0.1% (2.4% in Mt. Gumo) of the total collection. During the primary collecting periods from the middle of April to the end of November, the seasonal prevalence of the total flies showed a somewhat smooth pattern, except two distinct peaks appearing in the middle of May and at the end of August. When seasonal prevalence of three traps were compared, that of Trap 1 showed a pattern similar to that of the total fly collected. Although the overall pattern of Trap 2 was similar to that of Trap 1, there were some differences between them; the first peak of Trap 2 were extinct earlier than at Trap 1. The pattern of prevalence in Trap 3 was different from those in Trap 1 and Trap 2, and showed 3 peaks in the seasonal prevalence; the collection at Trap 3 was extinct at the beginning of November, earlier than at the other traps. The difference of the seasonal prevalence in each trap seemed to be due mainly to air temperature in trapping days among other environmental factors. The correlation between the total number of fly individuals and that of species collected at three traps was found to be very close. The number of fly species was 24 and 26 in May and August, when the collection peaked respectively, which represented about 67% of the total species collected. The charateristics of ten predominant species in the collection were summarized, and their seasonal prevalence and monthly change in the composition of flies collected at each trap were also compared.