This thesis examines how youth political representation affects voter turnout among young people and shapes both intergenerational and intragenerational inequalities in political participation. Existing research highlights the turnout-boosting effects of youth representation but often neglects variations within the youth population and the institutional contexts in which participation occurs. To address these gaps, this study employs multilevel logistic regression using cross-national data from 38 countries in the Comparative Study of Electoral Systems (CSES) Module 5. The results show that youth representation increases voter turnout among young people and reduces the generational turnout gap, yet its benefits are unevenly distributed. Young women and individuals with higher education levels experience greater gains, while effects are limited for lower-educated groups, and the urban–rural divide remains insignificant. Macro-level conditions such as GDP per capita and democratic quality enhance the inclusivity of youth representation, whereas income inequality and population aging exert mixed or minimal effects. These findings indicate that the impact of youth representation depends on the interaction between individual attributes and structural environments, forming a conditional inclusion structure that can either promote or constrain participatory equality. The study reconceptualizes descriptive representation as a conditional form of inclusion and argues that increasing youth presence in politics alone is insufficient without complementary reforms that strengthen education access, gender equity, and institutional trust to foster equitable youth participation.