Energy security has been a major concern in developing countries because of rapid economic development and population growth, low power generation capacity, and unwell-developed transmission infrastructure. Vietnam in this context has been under energy security threats for more than a decade and is currently having a new power policy to strongly develop power generation and distribution networks. It is expected that the country's economy is able to develop substantially due to massively additional energy supply once completing the plants and distribution networks but the likely impacts are still undefined. This paper extends an economic electricity-detailed model to examine the potential impacts of such a new power policy in Vietnam. We find that the policy will decrease the prices of both fossil-based and renewable-based electricity significantly by 40%–78% under a 2030 target scenario, benefiting all sectors in the economy to substitute for fossil fuels. Households are particularly benefited as evidenced by 5.64%-19.19% increases in per-capita utility. Overall, the Vietnamese economy is significantly advantaged with real GDP increasing by 5.44%-24.83% over different scenarios, which are much higher than the findings in other countries. More importantly, the policy moves the country to a low-carbon energy structure in the near future.