Abstract: The aim of this paper is to analyze the political trust of the “Post-80s” and “Post-90s” generations of young people in Hong Kong. The Age–Period–Cohort model is employed to examine the independent effects of age and cohort on political trust using data from longitudinal surveys conducted biannually from 1998 to 2014. The findings demonstrate that, with regard to political trust, age and cohort have an independent explanatory power. First, the relationship between age and political trust is curvilinear. When individuals reach the age of 21 to 30, their political trust declines. After the age of 30, their political trust grows. Their political trust is greatest when they reach the age of 56 and above. Second, people who were born in the 1980s or 1990s have a higher level of political trust than those born in earlier decades.