This paper conducts a counterfactual analysis to estimate the effects of college expansion on earnings and occupational prestige of the young in Taiwan. The study uses two datasets collected by the Panel Study of Family Dynamics and a DID model for analysis. The study uses matching to identify three counterfactual groups: "compliers," "always-takers," and "never-takers" and then uses the DID model to estimate the proposed causal effects. The findings show that compliers benefit from college expansion in both earnings and occupational prestige of both the first and the current jobs. Always-takers' advantages in their first-job returns have been negatively affected by the expansion. In short, college expansion narrows the gap in socio-economic status between always- takers and compliers but increases the gap between those with and without college degrees.