Southeast Asia holds great importance as an essential passage of the Belt and Road Initiative and a key node region for China's foreign trade.Here,the spatial and temporal characteristics of economic development of Southeast Asian countries from 2012 to 2021 are analyzed using NPP／VIIRS nighttime lighting data and spatial analysis methods such as centroid,standard deviation ellipse and Moran index.The results indicate a significant correlation between GDP and nighttime light data,and a generally northwest bound transfer of economic centers of Southeast Asian countries.Most of the nightlight clusters have moved 476 kilometers to the northwest of Southeast Asia (that is,to the land border between Southeast Asia and China),suggesting a relationship between the movement of economic centers and the Belt and Road Initiative.The overall economic volume of Southeast Asia has increased,and economic development has been clustering in the region with evident directional characteristics.In terms of the spatial features,high-high aggregation and low-low aggregation are the two most significant spatial aggregation characteristics.The high-high agglomeration areas have played a good role and driven the economic development of the surrounding areas,the low-high agglomeration areas have greater development potential,while the low-low agglomeration areas in northern Southeast Asia have decreased significantly during 2012-2021.