Objective In order to instrust rational application of antibiotics clinically.Methods Antibacterial activities of 8 antimicrobial agents against 20 strains of Ureaplasma Urealyticum (UU),20 strains of Mycoplasma hominis (MH) were determined using the broth dilution.Results Jasamycin was highly active against UU and MH for UU MIC 50 was 0.25mg/L and MIC 90 2mg/L,and for MH MIC 50 was 0.125mg/L and MIC 90 0.5mg/L,Doxycycline was active against UU(MIC 50 to MIC 90 ,4 to 32mg/L),whereas the MIC 50 to MIC 90 for MH was 2 to 4mg/L.Ofloxacin was active against UU,MIC 90 for MH was 2 to 4mg/L.ofloxaci...