Black carbon (BC) aerosol have important impacts on regional and global climate change. China and India are the world"s largest anthropogenic BC emitters. In this paper, the newest generation of regional climate model RegCM4 is used to investigate the direct impact of BC emissions from major areas of India and China on east Asian climate in winter. The results show that the total BC column burden, top of atmospheric and surface effective radiative forcing from east Asia are 1.784 mg/m2, +1.982 W/m2 and -2.170 W/m2, respectively. The influence of BC in China and India on regional climate is different. The Indian BC will cause the regional 850 hPa and surface cooling, while the Chinese BC will cause the regional 850 hPa warming and surface cooling. In addition, BC inChina has a stronger climate response in East Asia due to its higher emissions and wider distribution, and plays a leading role in regulating the regional climate in East Asia. In general, BC in both places will cause cloud cover to decrease by 0.21% near 850hPa, air temperature to increase by 0.014 K near 850hPa, sunshine duration to decrease by 0.135 h/day, surface air temperature to decrease by about 0.091 K, sensible heat flux to decrease by 1.161 W/m2. Surface evaporation decreased by 0.027 mm/day, boundary layer height decreased by 7.072 m, POA column burden decreased by 0.027 mg/m2, sulfate aerosol column burden increased by 0.035mg/m2. The results further suggest that the direct response of east Asian winter climate to different BC emissions is nonlinear.