This study was conducted to investigate the prevalence of subclinical mastitis and its contagious and environmental bacterial causes in dairy cows in Jos Metro polis of Plateau State. A total of 208 milk samples were collected aseptically from 52 lactating cows and subjected to the California Mastitis Tests (CMT). Milk samples were transferred into peptone water broth for enrichment, followed with bacteriological assays and biochemical identification of bacteria. Using R Commander version 3.6.2, data such as: breed, age, parity, lactation, and management system of cows were collected, and analysed to determine their relationship with bovine subclinical mastitis. Out of 208 quarter milk samples collected from 52 cows, 35.09 % showed subclinical mastitis. While the Cross-breed cows had 15 % subclinical mastitis recorded, the White Fulani had 78.13 %. Cows of the age 3 to 5 years had the highest prevalence of mastitis, while cows with 4 to 6 calves showed the highest prevalence in the parity category. The early lactation stage of these cows showed the highest prevalence. The environmental bacteria isolated where