This thesis aims to look at the fertility rates and the reasons leading to low fertility rate over Taiwan and some countries, in order to find the keys for stimulating fertility. The main reasons causing the decline in fertility in Taiwan include: The first, more and more women delayed their marriage, or decided never married; The second, social norms influenced by Confucianism culture make people are not willing to have a child if they do not get married. The two reasons lead to fewer new births over recent years. This research gives some suggestions for encouraging fertility rate: improving the rate of marriage, stabilizing the household income, increasing the amount of childcare subsidies, and allowing to increase the period of maternity leave and parental leave.