We develop the kinetic model of the dye adsorption in LC cells. The motion of dye molecules is considered as Brownian diffusion in the potential field, created near the surfaces due to the Van-der-Waals and electrostatic interactions, as well as specific liquidcrystalline effects, caused by the orientational and translational order parameter changes. On the boundaries, the absorption and desorption processes are taken into account with coefficients, which depend on the surface density of adsorbed dyes. The model shows that dark adsorption depends mainly on surface parameters, which determine the stationary adsorption and the relaxation time. Light irradiation reduces the surface barrier and increases the adsorption and desorption coefficients. As the result all of the processes are strongly intensified and the characteristic time of light-induced adsorption becomes essentially shorter than the time of dark adsorption. Dark and light-induced adsorptions depend on the director field because the surface orientation of LC affects the surface barrier and the adsorption/desorption coefficients.