Synanthropic flies are adapted to live in close association with human habitations and are capable of transmitting human pathogens either mechanically or biologically through this close relationship. This research determines the relative abundance of synanthropic flies within Makurdi metropolis. A large wooden fly trap box whose inside was lined with aluminum foil was constructed. A well-cut and fitted mosquito net was attached properly by the sides of the box and opened halfway on top and bait (stale fish and meat) was placed inside the box to attract flies to enter the box. The box was quickly covered with the remaining half of the mosquito net when a good number of flies had amassed sufficiently on the bait (stale fish). Flies were caught from four locations in Makurdi: Benue State University, Wadata market, Wurrukum market, and Akphehe Market. This setup was allowed to stand for 25-30 minutes to allow the flies to get attracted to the bait. And an insecticide was used to spray through the mosquito net to kill the flies before picking using forceps. A hand lens and disserting Microscope was used to examine flies which were then identified and sorted out into species using taxonomic keys (Greenberg, 1973). A total of 285 species of S. flies were sampled from different locations within Makurdi metropolis; wadata market, BSU, Wurukum market, and Akpehe market respectively. Identified species were Musca domestica (94.0%), Chrysoma putoria 15(5.3%), and Muca sorbens (0.7 %) respectively.Prevalence of Synatropic flies across sample locations were also evaluated in this study, result showed that wadata market had the highest prevalence 93(32.6%) followed by wurukum market 77 (24.9%) and BSU 44 (15.4%) respectively. Based on distribution, result showed that Musca domestica had the highest prevalence in both Locations given a total of 268(94.0), followed by chrysoma putoria 15(4.6%) while musca sorbeans 2(0.7%) had the least prevalence. This study illustrates the diversity of synanthropic flies collected in various human localities within Makurdi local government area of Benue state. Three species (Musca domestica, Chrysoma putoria, and muca sorbens) are identified as the most relative abundance of synanthropic flies within Makurdi metropolis. There is need to institute a functional control measures such as community health awareness and enforcement of strict environmental sanitation programme to reduce mechanical transmission.

KEYWORDS: Flies, Abundance, Synanthropic, Distribution, Pathogens and Diseases.