Abstract: A strain of Mycoplasma named GH2 was isolated successfully from lung tissues of sick goats in Hubei province. This isolate was purified several times and were identified by biochemistry test, microscope observation, PCR, REA, genome analysis and animal pathogenicity tests. The immunogenicity of outer membrane proteins and whole cell proteins of GH2 were analyzed by western blotting. The results were compared with antiserum of Mycoplasma mycoides subsp. capri and Mycoplasma ovipneumoniae. Result showed that the strain GH2 belongs to the Mycoplasma capricolum subsp. capripneumoniae (Mccp) and the proteins about 60 and 49.7 kD possess its capital immunogenicity and they were also the specific antigen of GH2 which distinguished with Mycoplasma mycoides subsp. capri and Mycoplasma ovipneumoniae. Result of this study lay good theoretical foundation for diagnosis and vaccine development of Mycoplasma capricolum subsp. capripneumoniae.