Objective  The purpose of the observation was to prove whether there exists an infection with   Mycoplasma genitalium(Mg)   in clinical specimens from the ant  patients by using the method of cell culture and the medium culture in Tianjin. Method  The clinical specimens taken from STD clinic patients by sterilized swab were cultured in SP  4 medium and Vero cell,respectively.The clinical strains whose characteristic features met the criteria for   Mg   were identified with meta~bolize inhibition tests,PCR and so on.Result  By the medium culture,there were 2 strains isolated from 79 clinical specimens with an isolation rate being 2.53%.By the cell culture,there were 5 strains isolated from 80 clinical specimens with an isolation rate being 6.25%.No significant difference was found between the results by the two methods (  χ    2 =0.57,0.25<  P  <  0.5  ).Conclusion  The existence of   Mg   infection was proved pathogemically in Tianjin.