Abstract: Objective To investigate the incidence of macrosomia in Suzhou,analyze the related factors of macrosomia,and provided basis for reducing the incidence of macrosomia. Methods The statistic data of macrosomia incidence has been acquired from regional health information platform.The case-control method was used to analyze the related factors of macrosomia.A total of 299 macrosomia cases were included in the observation group,while 300 cases of normal birth weight infants were included in the control group in the same period.By consulting medical history,the details about mothers during pregnancy and the newborns were investigated.SPSS 19.0 statistics software was sued to analysis the data. Results There was 86 178 cases newborn in 2014 in Suzhou,including 5 320 cases of macrosomiawith an incidence of 6.17%.The maternal situation between the two groups,including gravidity and parity,maternal age,pre-pregnancy body mass index(BMI),weight gain during pregnancy,gestational diabetes mellitus(GDM),mode of delivery and gestational age,has statistical differences.The unconditional multiple Logisitic regression analysis showed that weight gain during pregnancy was the main risk factors,followed by pre-pregnancy body mass index(BMI) and gestational diabetes mellitus(GDM);the male newborns,mode of delivery and gravidity was also related with the incidence of macrosomia. Conclusion ①The incidence of macrosomia in 2014 was lower than the average national level(7.3%),and lower than the 10.6% in developed economic regions of Anhui province.②The result shows that the dangerous factors of macrosomia including pre-pregnancy body mass index(BMI),weight gain during pregnancy,gestational diabetes mellitus(GDM),gravidity and parity,gestational age,and male newborns.③The pre-pregnancy education should strengthen to control pre-pregnancy body mass index;the guidance during pregnancy should be strengthen to control pregnancy weight;the appropriate exercise and balanced diet,and reducing the incidence of gestational diabetes mellitus should be regarded as the main intervention factors for the privation of macrosomia.