Houseflies (Musa domestica) are common insects of the families muscidae, order Dipthera. They are synanthropic insects that are widely distributed worldwide. They enter several places, including contaminated premises due to their own biological habit of feeding. This study identifies the pathogenic parasites and bacteria associated with the houseflies in Lafia, Nigeria. A total of 215 flies were collected from 5 locations (New market, Neigbourhood market, Kasuwan Turmatur, Kasuwan Karo and Yanlemu market) within the Lafia metropolis, from September, 2019 to March 2020. The fly specimens were analyzed for the presence of pathogenic parasites and bacteria using standard laboratory procedures. The results showed that the parasites: Entamoeba hietolytic was most prevalence with (22.11%) Ascaris lumbricoides being (15.05%), Taenia species (14.70%) schistosoma mansoni (14.70%), Hookworm and Trichnris trichura recorded least prevalence accounting for (1.12%) respectively, pathogenic bacteria isolated and identify from the houseflies are; Staplyloccus sp (36.36%), Bacillus species (19.48%), Klebsiella sp (19.75%), Escherichia sp (6.49%), Protens sp (7.41%), Salmonella sp (6.49%) and Moraxella sp (2.47%). The result showed significant variation (P0.05) associated with the frequency of occurrence of bacteria species. It can be concluded that Musca domestica in Lafia harbor parasites and bacteria on their external and internal parts. The housefly have mechanical potential to transmit pathogens to man. Measures most be taken to control the fly population to avoid both present and future outbreaks of diseases condition emanating from the flies activities.