The signing of the Kuala Lumpur Declaration on 22 November 2015 by the ten ASEAN members has reaffirmed the goals of the ASEAN Economic Blueprint 2015 and its objectives towards fulfilling the 2025 Blueprint for an ASEAN single market. Currently, works are in progress on regional competition law based on the ASEAN Regional Guidelines on Competition Policy drafted by the ASEAN Experts Group on Competition (AEGC). At the national level, nine of the ten ASEAN member states have enacted their competition laws. While this is an encouraging development of ASEAN competition law, with the parallel development on ASEAN market integration, many challenges remain. One important concern, which is the focus of this paper, is the presence of State-owned enterprises (SOEs) in the ASEAN member states. SOEs, occupying positions of market dominance and enjoying government support, can create difficulties to the application of national and ASEAN competition law, thereby slowing the process of ASEAN market integration. This paper evaluates the impact of SOEs on ASEAN’s pursuit towards market integration with particular reference to Singapore, Malaysia and Thailand.