The "One Belt, One Road" (OBOR) initiative—Chinese President Xi Jinping's signature project and strategic master plan that promotes infrastructure connectivity with foreign countries—has been widely discussed in academia and the media since its launch in 2013. The OBOR's engagement in Southeast Asia is evident in terms of infrastructure development projects, economic and trade cooperation zones, port construction and industrial cooperation. This article explains the role Southeast Asia plays in the progress of the OBOR (now commonly known as the Belt and Road Initiative [BRI]) projects, which are also aligned with the ASEAN (Association of Southeast Asian Nations) connectivity master plan and domestic policies of individual ASEAN countries. Southeast Asia's significance in the BRI's development could be viewed from the following aspects: the geoeconomics and geopolitical consideration in the region, as well as the contribution to potential growth of China's internal industrial and economic development. However, China should review its model of investment—in terms of the nature of projects, form of cooperation and the domestic political development of ASEAN countries—as Southeast Asian countries have found Chinese practices and motivations questionable.