Abstract: Objective To study on the effect of seven kinds of infectio us disease on health from the a spect of healthy life year.Methods Using DALY to analyze the loss of healthy life years in populations of different age,different gender and different areas caused by infectious diseases(three contributors of AIDS,hepatitis B,hepatitis C,measles,diarrhea,tuber culosis,syphilis)in 2005 in China.Results The first three DALY were tuberculosis,syphilis and hepatitis B(0.8228,0.0768 and 0.0539)among the seven infectious diseases.Different diseases had different DALY component.The DALY due to AIDS and diarrhea were mainly caused by death,but that of tuberculosis and syphilis were caused by disability.The DALY of tube rculosis wasmostly contributed by the age group of over 70 and that of AIDS by the age group of 30-44 and the measles and diarrhea by the age group of 0-4.The DALY of male was larger than that of female.The DALY of tuber culosis in the north west,of syphilis in the east,of AIDS in Yellow River area was 1.0687,0.2146,0.1104 years perthou sand,respectively.Conclusion Among the seven infectio us disease ,stuberculosis contribute the greatest mipacton health.The DALY of AIDS and diarrhea wasmainly caused by death,but that of syphilis,tuberculosis and hepatitis B was caused by disability.The DALY of male is larger than that of female except for syphilis.The DALY of tubercu losis in the north west is the highest all over the country.