This paper examines issues relating to Japan's digital advance policy (DAP) for ASEAN countries during the period 2015 -2019, which aimed at broadening the spectrum of digital economic growth. The study sought to gain insights into the impacts of respective policies of ASEAN, Japan Council for Science, Technology and Innovation (CSTI), Japanese digital foreign direct investment (FDI), and Japanese enterprises. The study also examined workflow structure processes to explain how Japan's DAP contributes to ASEAN's innovation business. This research is categorized as a reconnaissance study, based on empirical analysis of pertinent existing evidence, complemented by 74 in-depth interviews with key experts from ASEAN, JICA, CSTI and major digital enterprises from 5 ASEAN countries. The findings indicate a need to redirect the innovation business of Japan's DAP as well as ASEAN's innovation business and to enhance their mutual alignment. Four key entry points are proposed: (1) policymakers, (2) private sector businesses, (3) goalkeeper science, and (4) innovative infrastructure. This paper also provides guidelines and support to validate key performance indicators of Japan's DAP in ASEAN countries. The studies how Japan's digital holistic platforms could be transferred to ASEAN countries under the DAP. It also examines the relationship between key performance indicators of Japan's outward FDI in ASEAN digital businesses and growth in ASEAN's innovation business.