Research Professor, Institute for East Asian Studies at Sogang University This paper examines how Thai youth activism, grew out of student-led democratization movements that culminated in the victory over the military dictatorship on October 14, 1973, has attempted to reduce the influence of royalist democracy and widen the political discourses from below. Their endeavor eventually led to a victory of the Move Forward Party in the 2023 general election. For a sharper analysis, the paper compares the generational shifts in the political opinion leaders and their increasingly radicalizing social reform demands in the 1970s and 2020s. The first part surveys the historical development of Thai youth activism from the People’s Party revolution in 1932 to the expansion of youth-led democratization movements until the 2023 general election. The second part begins with analyzing the 2023 election results to delve into the social reform demands presented during the election campaign. Based on this analysis, the paper argues socioeconomic and political factors derived from persisting inequality and hierarchical structure in Thai society contributed to the radicalization of the youth movements especially during the global pandemic. The Thai youth’s conversation with the past victory over the authoritarian regimes led to diversifying their social reform demands at present.