Using geostrophic calculations with a quasi-zonal CTD section obtained between 38-40$^o$N in summer 1999, and velocity estimates at 700 m level from autonomous profiling floats (Argo floats), we investigate the structure of meridional mass and heat transports in the East/Japan Sea. In the horizontal, due to eddies and the meandering of the polar front, the flow changes its direction almost at every 100 km or so. In the vertical, although the flow becomes with depth the direction of the flow does not change suggesting the importance of the bottom topography even at the surface. The total volume transport though the CTD section is 1.6 Sv., which is significantly less than the volume transport through the Korea Strait, which is around 2.5 Sv., because the CTD section does not cover the strong and narrow current along the Japanese coast (the Near shore Branch). Water colder than 10C is due to it own thermohaline circulation of about 0.9 Sv. The total meridional heat transport thought the section is 0.15 PW of which about 43% is due to its own thermohaline circulation. The meridional mass transport due to the surface wind stress across the CTD section is less than 10% of that due to the geostrophic flow, and so dose the heat transport.