In this dissertation, SnO_2 as a substrate, Ni and Nb were co-doped by sol- gel method and spin coating technique to prepare its thin-film samples.The thin film samples were characterized by XRD, SEM, XPS, FTIR, four-probe resistivity meter and spectrophotometer instrument. The results showed that: 500 ℃ preparing a higher degree of crystallinity tetragonal rutile SnO_2: Ni composite film, SnO_2: Nb composite film and SnO_2:Ni, Nb transparent conductive film. Films surface smooth, uniform particle distribut...