This paper uses firm level data to examine the market concentration of Korea’s food processing industry by measuring the concentration ratio indices of each detailed industry. Moreover, the fixed effects models are used to investigate potential factors influencing the market concentration indices of the food processing industry. The variables such as minimum efficient size (MES), advertising concentration index, required capital ratio, industry growth ratio, firm entry ratio were selected as the major factors. The results found that the minimum efficient scale is positively related to the market concentration of the food processing industry. Also, the required capital ratio and advertising concentration ratio are positively related to market concentration, indicating those factors act as barriers to entry for new businesses.