Abstract: Objective To explore the risk factor of female breast cancer for the prevention of the disease.Methods With matched case-control method,a survey was conducted among survival cases of histologically diagnosed breast cancer patients and control cases of inpatients of injury in three grade Ⅲ-class A hospitals from January to December,2007 in Harbin city,Heilongjiang province.The SAS was used to conduct logistic regression and single factor analysis on risk factors.Results Multiple factors analysis showed the relevant factors of breast cancer were abortion times (OR=1.63,95% CI=1.23-4.15),family history of malignancy (OR=3.33,95% CI=1.95-5.55),body mass index (OR=1.78,95% CI=1.15-5.09),mental stimulations (OR=2.49,95% CI=1.75-4.44),age at menarche (OR=0.62,95% CI=0.31-0.88),breast nursing time (OR=0.83,95% CI=0.42-1.00),number of birth (OR=0.64,95% CI=0.31-0.97),the frequency of fruits intake (OR=0.53,95% CI=0.32-0.89),the frequency of vegetable intake (OR=0.35,95% CI=0.14-0.74).Conclusion Abortion times,family history of malignancy,greater BMI,mental stimulations are the risk factors of breast cancer.Old age at menarche,breast nursing time,number of birth,the frequency of fruits and vegetable intakes are protective factors of breast cancer.