Counterimmunoelectrophoresis (CIEP) is a reliable specific technique for the diagnosis of mycoplasmal mastitis and more sensitive than other methods. It was found that the isolation procedures of 180 examined milk samples could reveal 62 (34.44%) strains of M.bovis and 34 (18.89%) of M.bovigenitalium, while CIEP technique revealed 65 (36.1%) as M.bovis and 37 (20.5%) as M.bovigenitalium. However the results obtained from the examination of tissue samples by either method were the same. In addition, the CIEP is more rapid as compared to the laborious and time consuming standard cultural method.