Electrification of road transport (or electric mobility) has progressed beyond the demonstration stage, with many Association of Southeast Asian Nations (ASEAN) members increasingly interested in it. This study starts with a survey of all ASEAN countries' vehicle fleets, fuel consumption and share, fuel mix in power generation, among others. The potential of electrifying fleets, including passenger vehicles, buses, and trucks the main consumers of fossil fuel in road transport is estimated in 2040 scenarios. How electric mobility enhances energy security is assessed using the 4A framework: availability, applicability, acceptability, and affordability of energy. The findings reveal intensive interaction of electrification of road transport with the introduction of higher fuel economy standards and higher integration of renewable energy into the power sector.