Over the past few years, many innovative vaccines became available that offer protection for diseases which have never been prevented before. While there are several factors that could have an impact on access, the use of health technology assessment (HTA) undoubtedly is also one of the contributing factors. Objectives: To explore the landscape of vaccine access and the role of HTA in new vaccine adoption in Association of Southeast Asian Nations (ASEAN) countries. Results: A great deal of progress has been made in terms of access to new and innovation vaccine in the region. Variation in access to these vaccines comparing between countries, however, is still observed. The use of HTA in supporting new vaccine adoption is still in an early stage especially in Gavi, the Vaccine Alliance-eligible countries. Conclusions: Improving the use of HTA evidences to support decision making could accelerate the efficient adoption of new vaccine in ASEAN region.