Staphylococcal Coagglutination was used as method for a rapid identification of mycoplasmas that could be performed by non specialized laboratories. Suspensions of Staphylococcus aureus (Cowan I) sensitized with rabbit antibodies against NCTC mycoplasma strains have identified these microorganisms and the strains isolated from humans, cell cultures rats and mice in concentrated suspensions from cultures of 4.0 ml. Fourty eight strains of M.pulmonis, 6 of M. arthritidis, 8 of M.arginini, 3 of M.orale, 15 of A.laidlawii, 8 of M.hominis and 3 of M.pneumoniae were identified by staphylococcal coagglutination and confirmed by Growth Inhibition Test. Optimal parameters of coagglutination were established and the stability of the conjugates were preserved for 90 days when added with acetyl cysteine. The reaction was visualized without optical resources. The sera were previously absorbed with heterologous NCTC strains and with the pellet of the sterile broth.