Abstract Inflammation of the mammary gland is a disease of great importance in milk production that generates significant financial losses worldwide. This study pretends to determine the occurrence, predominant pathogens, and risk factors associated with clinical mastitis in the province of Ubaté. The research required the design of a twenty-four-month longitudinal epidemiological study. Data from 504 small producers, 4233 animals in production, 133 mastitis clinical cases, and 53 microbiological cultures were analyzed using binary logistic regression models to establish the association between possible risk factors and disease. Results. The disease had an incidence rate per animal and per quarter between 2.0–4.0 and 0.6-1.0 new cases per 100 animals-quarter-year at risk. The most prevalent microorganisms isolated were Coagulase-negative staphylococci and environmental streptococci. The cow and quarter level risk factors identified were dirty mammary glands, hyperkeratosis, and nipple wounds. Herd-level risk factors include workwear exclusively for milking, the prevalence of subclinical mastitis, milking method, cleanness of the workwear, the water source used during milking, use of gloves, correct use of disinfectant, pre-milking management, handwashing before milking, and foremilk disposal. Conclusions. Preventive programs should aim to control risk factors related to hygiene and milking routine since these were associated with the presentation of clinical mastitis caused by environmental microorganisms that were the most prevalent in cows affected in this study.