Abstract:  Nurhachi and Huangtaiji enacted the coastal evacuation measures to diminish the threatof Ming sea power. At the same time，the evacuation stabilized their rule in the area east of the Liao River. This laid the foundation for national unification and pioneered the Coastal Evacuation of the early Qing dynasty.This maritime policy and the preventive measures of the Huang Taiji period determined the administrative areas and ethnic distribution patterns in the northeast area.