The epitaxial Sm_xNd_1-xNiO₃ (x=0.5, 0.55, 0.6, SNNO) thin films with (001)-oriented single-crystal LaAlO₃ substrates were fabricated by a chemical solution deposition technique, namely polymer-assisted deposition (PAD) under the ambient oxygen annealing. X-ray diffraction θ-2θ scan, rocking curve measurement, φ-scan and scanning electron microscopy were used to study the SNNO characteristics. The results reveal the good crystallinity and heteroepitaxy of these SNNO films. Temperature dependence of the resistivity indicates that all the films show a clear Mott metal-insulator transition (MIT) and the transition temperature (T_MI) shifts to higher temperature with the increase of Sm content. The epitaxial Sm_0.55Nd_0.45NiO₃ thin films exhibit MIT near room temperature. The successful growth of high quality SNNO films with room temperature transition by economic and facile PAD method shows great potential in practical application of nickelate.