With rapid economic and social development in China,the number of floating population is gradually increasing. The issue about maternity security of floating population has caused wide attention in society. Based on the research of floating population in Nanjing,Suzhou and Wuxi in Jiangsu province,this paper analyzed the current situation of maternity security about floating population,discussed the influencing factors of the benefit level they get from maternity insurance by using Logistic model. The results showed that the rate of the floating population’s participation in maternity insurance in the three areas was lower than the local level,and the relevant policy had not fully implemented. The benefit level the floating population had get from maternity insurance mainly influenced by age,level of education,the situation of employment during the birth,the importance of maternity insurance,the areas and popularity on fertility security knowledge of the employers.