The current study aimed to analyze offspring birth plan according to different variables of working mothers with one child and its effects on parenthood. The research sample was from the second data of 2nd year Korea Child Panel from Korea Institute of Child Care and Education. A total of 296 mothers were selected for the study. To analyze the data, chi-square and logistic regression were used using the SAS 9.0 computer program. The results were as follows: First, offspring birth plan to have a second child depended on the age of the parents. Second, conflicts between a couple, the emotional and instrumental value of having a child, the stress of upbringing had an effect on their second child birth planning. In conclusion, various aspects such as parent education programs were considered to improve the fertility rate.