Objective To understand the anti-leptospira antibody level and bacterial distribution in the serum of healthy people and host animals,so as to provide scientific basis for prevention and control of leptospirosis. Methods Serum samples were collected from healthy people and host animals,and tested for antibodies to 15 leptospira serovars using the microscopic agglutination test( MAT). Results From 2007 to 2011,serum samples were collected from healthy people and host animals,such as the rats,ducks and dogs. The average positive rates of anti-leptospira antibody were 16. 53%,23. 95%,4. 98%,12. 15%,respectively. The main serotype was Leptospira autumnalis in human beings and dogs,which was Leptospira ballom in rats and Leptospira Hebdomadis in ducks. The rat density was 8. 66% and the dominant species was rattus norvegicus. Conclusion In the three host animals,the positive rate of rat serum was the highest,indicating the rats were still the main source and key monitoring object for leptospirosis epidemic. The rat density is high,so there is still a risk of leptospirosis epidemic.