Abstract: Objectlve ThiS study was conducted tO bettor understand the incidence rate of acute Infectious diseases and their changing trend and provide a scientitle basis for the formulation of strategies for the prevention and control of the 1nfectious diseases．Methods the descriptiVe epidemiological method was adopted，and analysis was made On the data of epidemic situation of infectious diseases in Yizhang city from l960 to 2004．Results In the Period of 45 years from l960 to 2004 the average annual incidence of infectious diseases was 1769.51/100.000 and mortality of the diseases was 5.78/100.000，with malaria，dysentery and measles being tie top 3 infectious diseases in terms of incidence It was showed that the incidence of infectious diseases was the bighest in 1970S After 1980s it decreased by a large margin with an unceasing change in the spectrtrum of infectious diseases Conelusion Substantial progress has been made in the prevention and treatment of infectious diseases and the incidence of infectious diseases related to planned immunization meets the natlonal criterion．And currently stress should be put 0n the prevention and control of enteric infecfious diseases and sexually transmitted discase (STD). Prevention and control of other infectious diseases still need to be strengthened．