Embedding nonlinear media in the slit region of metallic nano-optic lens is proposed as a new method of active modulating the output beam. Two important phenomena, beam deflection and focusing, have been studied in detail. A developed Finite Difference Time Domain (FDTD) method has been performed to account for the nonlinear response. The simulated results show that the deflection angle and focus length can be controlled easily by the intensity of incident light in the structures. The physical principle of the phenomena is explained by the Surface Plasmons (SPs) excitation and Fabry-Pérot (F-P) resonance in the nanoslit.