The synoptic behavior of present-day heat waves (HW) over East Asia is studied using a global high-resolution atmospheric model (HiRAM) with 50-km grid-spacing. The simulated HW characteristics are compared with those derived from Climate Forecast System Reanalysis products. Additional runs of HiRAM are conducted for the "time slice" of 2086-2095 in the climate scenario corresponding to Representative Concentration Pathway (RCP) 4.5. By the end of the 21st century, the averaged duration and frequency of HW in selected East Asian sites are projected to increase by a factor of 1.4-2.1 and 2.0-2.3, respectively, from the present-day values. The output from a continuous integration of a coupled general circulation model with a lower resolution through the 1901-2100 period indicates a notable increase in severity, duration and HW days during the 21st century.