Oil-water-surfactant mixture is investigated near the planar surface by mean-field theory applied to a certain lattice model. Close to the coexistence of the microemulsion with the lamellar phase, the model predicts either surface-induced ordering or surface-induced disordering transitions, depending on the nature of the surface. The new order-parameter, describing the lamellar order, is defined. The Landau-Ginzburg functional based on the new "lamellar order parameter'' is introduced. The functional has a form introduced earlier for surface-induced ordering and disordering in simple fluids. Connection of the continuous model to the lattice one is discussed.