Abstract: The Socialist Republic of Vietnam is a socialist country ruled by the Communist Party of Vietnam whose leading ideology is Marxism-Leninism and Ho Chi Minh Thought. The country adopted a new constitution in 2013. This article argues that the Constitution is not purely socialist but mixed. It explores the condition, structure, and consequence of this mixed Constitution. The conditions are: internal social complexity shaped by three decades of social and economic reforms; external diffusion of constitutional ideas due to globalization. The structure of the mixed constitution includes: ideational mixture (liberal, Confucian, socialist, and universalist); and institutional mixture (centralized, distributed, and controlled powers; statist, communitarian, liberal, universalist rights; and the socialist-market economy). The latter is the embodiment of the former. The mixed constitution widens space for the dynamics of public constitutional discourse in Vietnam.