Contagious agalactia caused by Mycoplasma agalactiae is an economically important disease of sheep and goats which is prevalent worldwide including India. The isolation of organism is tedious and time consuming and only the serological tests, considered to be the most suitable for screening the herds but have certain limitations, especially on using whole cell antigens as the cross-reactive epitopes resulting in the false positive reactions. Therefore, the present study was undertaken to evaluate the membrane protein P80 of Mycoplasma agalactiae for specific diagnosis of disease in sheep and goats.