We compare the prioritized projects of the Master Plan on ASEAN Connectivity (MPAC) and the Comprehensive Asia Development Plan (CADP) by utilizing the Institute of Developing Economies/Economic Research Institute for ASEAN and East Asia Geographical Simulation Model. The prioritized projects of the MPAC mainly focus on specific hard or soft infrastructure projects connecting one remote area of an ASEAN member state to another and thus fail to capture the full potential of the infrastructure because of neglected important links within a state. On the other hand, the CADP emphasizes the importance of economic corridors or linkages between a large cluster and another cluster. Our simulation analysis shows that CADP projects will result in an addition to gross domestic product (GDP) of $US 1544bn over the period from 2021 to 2030 (in 2010 dollars) or an impact on ASEAN countries that is 12 times larger than MPAC projects. The results strongly suggest that the CADP projects should be adopted and implemented to fully realize the potential economic growth of the ASEAN countries. Moreover, the CADP will contribute more to narrowing the development gaps among the ASEAN countries than MPAC prioritized projects.