This article explores the social mechanisms connecting national identity and support for democracy. Our investigation centers on the mediating role of civic beliefs and participation, employing data sourced from the European Value Survey (EVS 2017), which encompasses a total of 36 countries. First, our findings reveal a positive effect of voluntary (civic) national identity and support for democracy and a negative effect of non-voluntary (ethnic) national identity on support for democracy. Second, mediation analysis shows that individuals with higher levels of voluntary national identity exhibit stronger civic beliefs and participation, contributing to pro-democracy attitudes. In contrast, we find that non-voluntary national identity is inversely associated with civic beliefs and participation, largely explaining the negative effect on support for democracy. Although the mediators do not entirely account for the relationship between national identity and pro-democracy attitudes, they are important in shaping the relationship.