Decision No. 1658/QD-TTg dated October 1, 2021, of the Prime Minister approving the National Strategy on Green Growth for the 2021-2030 period, with a vision to 2050, has identified the green economy as a strategic orientation that Vietnam must aim for. To ensure the success of this strategy, the State must use many tools as driving forces, such as finance, technology, communication, and education, and especially indispensable legal tools. The law, on one hand, must have a guiding effect through regulations paving the way to encourage investment and development, and, on the other hand, must have a higher deterrent effect through strengthening and ›facilitating litigation mechanisms towards sustainable environmental protection. A class action is a legal mechanism that allows a group of people with similar interests to jointly sue a defendant through common representation. This model is particularly effective in environmental cases, where the damage is often widespread and affects a large community. In some countries, class action with an opt-out mechanism has been recognized for a long time, but in Vietnam, the current law has not yet fully recognized the right class action mechanism, especially in the environmental field. In fact, the 2015 Civil Procedure Code and the 2020 Environmental Protection Law have some fundamental provisions on collective lawsuits that, however, need to be improved. Learning from the United States’ legal model will help Vietnam perfect the class action model in the future, aiming to protect the environment more effectively and fairly. The paper uses the methods of analysis, comparison, and synthesis to achieve the above research objectives.