We used the 2016 Hong Kong Census data and the diagonal reference model to investigate the effects of partners' educational pairings on fertility in Hong Kong. Our findings suggest a negative relationship between couples' educational achievements and their fertility. Moreover, males' educational attainment is more consequential of whether having children or not and both males' and females' educational attainments are determinants of the number of children to raise. In addition, the more educated a wife is relative to her husband, the less likely the couple is to have children. Once these educationally hypogamous couples have at least one child, they tend to have fewer children than their homogamous counterparts. By contrast, couples with a relatively more educated male are more likely to have children and tend to rear more children than those in educationally homogamous marriages.
