This study was conducted to analyze the reasons for and advantages and disadvantages of implementing the HACCP (Hazard Analysis Critical Control Point) system on animal farms in Korea. The study was carried out by randomly selecting 45 swine and 24 dairy farms where HACCP has been implemented. The results were as follows: 24% of the swine farmers responded that extension of their business was the major reason for implementing HACCP; the second (21%) was financial support from local or national government. Dairy farmers had similar responses. The top advantage of adopting HACCP was improvement of the welfare of employees in both swine (21%) and dairy (22%) farms. The first-ranked disadvantages of HACCP implementation were HACCP education (23%, swine farm) and high turnover of employees (24%, dairy farm). On farms, HACCP may increase the sanitation and safety levels of domestic livestock products. However, the Korean government should address the disadvantages of HACCP to encourage its adoption at the animal production stage.