Mastitis is the most costly disease of dairy industry throughout the world. Sub-clinical mastitis is not observed by the farmers but results in hidden losses in terms of production. The present study was conducted to determine the quarter wise and animal wise prevalence of sub-clinical mastitis in buffaloes in Attock district of Punjab, Pakistan. Milk samples were collected from apparently mastitis free 1200 quarters of 300 buffaloes. The samples were subjected to Surf Field Mastitis Test (SFMT). The overall quarter wise prevalence was 58.75 percent, while animal wise prevalence was 77.98 percent. The maximum quarter wise prevalence was found to be 16.66 percent in Tehsil Jand, followed by 13.33, 11.67 and 13.33 percent in the tehsils Attock, Pindighaib, and Fateh Jang, respectively. The maximum animal wise prevalence was 82.61 percent in Tehsil Pindighaib, followed by 73.33, 80.00 and 76.00 percent in the tehsils Attock, Jand and Fateh Jang, respectively.