Highly conductive Pt-added LaNiO 3 composite films were fabricated by radio frequency co-sputtering method. Pt content dependence of microstructure, surface condition and electrical resistivity for the films were investigated. X-ray diffraction analysis shows that the composite films maintain the (001)-oriented structure until the Pt content exceeds 36.1at.%. Increasing the Pt content will increase the film surface roughness and higher Pt content results in the Pt hillocks with (100) basal plane formation on the film surface. Transmission electron microscopy observation reveals that with increasing Pt content, dense LNO grains are broken up and tiny Pt grains begin to emerge, join each other, grow up and finally agglomerate. Electrical measurements indicate that the film resistivity is greatly reduced with Pt addition.