Various factors negatively affect poultry production, including a multitude of avian pathogens. Among them, Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) cause world-wide economic losses in the poultry industry. Although respectively, MG and MS induce chronic respiratory disease and synovitis in poultry, these pathogens often manifest as clinically inapparent infections and many countries are therefore having difficulties effectively eradicating them. In this study, five broiler breeder farms in Korea were investigated for the presence of Mycoplasma infection from 2016 to 2018. Serum samples were collected for detection of antibodies to mycoplasma species using an enzyme-linked immunosorbent assay (ELISA) kit. Additionally, the production index and feed conversion rate of broilers were recorded. According to this investigation, broiler breeder farms in 2018 were serologically negative for Mycoplasma infection with broilers exhibiting a high production index and low feed conversion rate. Thus, eradicating mycoplasma in poultry farms is critical for improving chick quality and overall poultry production.