This study examines the impact of mate selection on premarital cohabitation and analyzes the influential mechanisms. “Introduced” and “self-initiated” mating are two main types of mate selection in mainland China. Since the start of reform and opening-up, “self-initiated” mating and premarital cohabitation has increased concurrently. This study develops hypotheses based on Chinese context and uses three-wave data from China Family Panel Studies (CFPS) to examine how different types of mate selection affect premarital cohabitation by performing logit models and propensity score analysis. The results show that compared to couples introduced by others, couples who have met through self-initiation are more likely to cohabit before marriage, especially in less developed areas. These findings suggest that the changing pattern of mate selection from “introduced” to “self-initiated” mating has driven the emerging premarital cohabitation in mainland China.