This study included 200 cattle and buffaloes in Mosul city from August 2025 to January 2026 to detect microfilariae in cattle and buffalo blood using Knott’s technique, Giemsa stain, fluorescent acridine orange stain, and Hematoxylin and eosin stain, Leishman stain. Three types of infection were detected including: mild, moderate, and severe using the same method, with significant differences (P < 0.05). The percentage of Microfilaria infection in blood was 40% in cattle and 60% in buffaloes. Results indicated a low rate of infection below one year old (26.7%) in cattle and (40%) in buffalo while a high percentage of infection in animals over three years old (55%) in cattle and (75%) in buffalo. significant differences were observed A high percentage of infection in females (45.5%) in cattle and (66.7%) in buffalo while the percentage of infection in males (33.3%) in cattle and (50%) in buffalo. The relationship between animal husbandry and infection rates indicated an increase level of infection in outdoor systems (46.2%,64.3%) in cattle and buffalo respectively than in indoor systems (28.6%, 50%) in cattle and buffalo respectively. The relationship between the months and infection rates diagnosed that presences an increase in the level of infection in summer seasons in cattle and buffaloes (61.1%,80%) respectively than in winter seasons in cattle and buffalo respectively (12.5% ,26.67%). Geographical distribution of the infection reviled that the higher infection rate observed in Badush region than anther regions in both cattle and buffalo (60%,72%) respectively.