A mega port is a necessary driver of the country’s economy and its population. Despite its significant economic impacts, the mega port also creates numerous social impacts, both during its construction and operation phases. The quality of life of people living in the port’s vicinity is inevitably affected. To attain sustainable port development and improve people’s well-being at the same time, mitigation measures stated in the environmental and health assessment report need to be strictly followed. Since a mega port is constructed once in many decades, a case study like this article is very rare. The authors present how Thailand took care of local people’s life quality during an expansion of its biggest container port (Laem Chabang Port, phase 3). The reclamation construction to expand the port started in May 2021 and is expected to be completed in 2025. This article shows that the Thai government and the joint venture contractor of the reclamation project realize the need to care for society and the environment.