This paper describes the relationship between the coherent structures and heat and mass transfer mechanism near a flat free surface in a fully developed turbulence. We use a direct numerical simulation of three-dimensional Navier-Stokes equations to identify the coherent structures in the turbulent flow. Fully developed turbulence statistics in a region close to the free surface are estimated to understand the peculiarity of the free surface turbulence. The evolution of the coherent structures and the velocity distributions around the coherent structures are discussed. In addition, the passive scalar field is imposed on the turbulent flow to clarify the relationship between the coherent structures and the scalar transfer mechanism into a turbulent liquid.