Epitaxial La0.85Na0.15Mn1-xNixO3 (0 <= x <= 0.2) thin films are fabricated successfully on LaAlO3 (LAO) (100) substrates using chemical solution deposition method. The results reveal that with the increase of the Ni-doping content, the X-ray diffraction intensity ratio of /((111))//((200)) increases, whereas both the grain size and the roughness decrease. The magnetic and transport measurements show that it is effective to tune the MR effects via Ni doping at Mn-sites.