The problem of scattering of plane electromagnetic wave on the infinite microstrip lattice with nonlinear loads in the strip plane was solved when a metamaterial (MM) is used as lattice substrate. It is shown that an application of MM as a substrate (instead of a dielectric) provides alignment of levels of the higher harmonics in comparison with first harmonic in the reflected field. It is reached due to suppression of fundamental harmonic in the reflected field. Also it is shown a possibility to increase the efficiency of the infinite microstrip lattice with the nonlinear elements, with a using of MM as a substrate, by means of a constructive synthesis of the geometrical sizes of the lattice.