Through the research of planned behavior theory， the questionnaire on two?child fertility attitude was compiled. Questionnaires were distributed to young women who had children in the counties of SQ city and LY city in northern Jiangsu Province. The average score of “giving birth to a second child causes family conflicts”， “increasing the burden of time and energy” and “affecting personal career development” in this project were all lower than a score of 2.6. The better the self?evaluation of the family’s economic status， the more positive has been shown towards the positivity of having asecond?child （P<0.001）， negative attitude is for those parents with a lower degree such as junior high school （P=0.003）， and the willingness of having a second child for full?time employment mothers is lower than that of other types（P=0.006）. There are non?deterministic causal relationships among the fertility intention， behavior and the attitude towards having a second child （P<0.001）. The government should carry out targeted publicity and education for boosing the birth of two?child， and formulate supporting policies for two?child birth as soon as possible. In particular， preferential policies for women in employment， medical treatment and education for infants and young children should be implemented， so as to effectively ease the pressure on young women to have more than one child.