The article aims to provide an overview of the trends that exist in the law on freedom of belief and religion in Vietnam. To achieve this goal, the author studied a system of legal provisions on freedom of belief and religion in each period of Vietnam's legislation since the birth of the Democratic Republic of Vietnam in 1945, pointing out the cross-cutting issues connecting these periods. The author uses methods such as analysis, synthesis, and comparison. Research results show that there are 4 common trends: Approximating to the provisions of international law; ensuring "equality" in enjoying the right to freedom of belief and religion; promoting religious activities that contribute to social development; and building a harmonious relationship between the state and religion. These trends both reflect the characteristics of Vietnamese legal culture and religious policy and clarify the duties of the law in the context of building and developing Vietnamese society. This article not only contributes to affirming the success of the law on freedom of belief and religion but opens the ways for the process of completing this legal content.