China's higher education system has expanded rapidly since 1999. Exploiting variation in the density of university expansion across provinces and high school cohorts and applying a difference-in-differences model, we estimate the impact of higher education expansion on educational access and attainment with a particular focus on students' family and demographic backgrounds. Results indicate that the expansion of university spots increased both access and graduation rates at 4-year universities, but this improvement was driven by those of higher social status, including males, those with highly educated fathers, han-ethnic and urban students. Females, rural students and those with low-educated fathers also benefited once they were able to graduate from high school. Also, the policy had only a limited effect on the likelihood of graduating from high school. As in other countries, education expansion in China has not led to equal distribution of educational opportunities, and the least socioeconomically advantaged students are missing out.