Abstract: Objective The present study was conducted to get the knowledge of the epidemic laws and changing trend of STD in Gansu Province through all epidemiological analysis of STD in Gansu Province in 2005，thus to provide basis for establishing strategies for prevention and control in the future．Methods Statistical analysis was used to investigate reported data on the epidemic situation of STD in 14 cities/prefectures from 1995 to 2005．Results In 2005．Totaled 5362 cases with eight types of STD were reported in the whole province and the reported incidence rate was 20.28/lakh，which decreased 9.44％ compared to that of 2004．From 2000. It was shown that re-ported cases with STD and its incidence rate were bOth in a down trend．While reported cases with LGV，Syphilis，HIV infection and Chancroid increased．Conclusion the decrease in the epidemic situation of STD iS superficial. And the actual situation is that the epidemic situation iS in an up trend according to the survey analysis．Propaganda and education should be reinforced as well as administration and rectification in the future．And the diagnosis and treatment of STD and the pre- vention of AIDS should be strengthened．