The p-n junctions had been fabricated by depositing La0.9Ba0.1MnO3-delta) (LBMO3-delta) thin film on the Nb-doping SrTiO3 (STON) substrates. Good rectifying properties of the LBMO3-delta/STON p-n junction have been confirmed in the temperature range of 70-300 K. It is found that the photovoltage (V-oc) peaks increase with increase of laser energy and temperature. The thermal excitation effects and the reduction of conduction-band mismatch with the rising of temperature are suggested to be responsible for the more carriers accumulating at edges of depletion layer, as well as the enhanced V-oc peak. (c) 2008 Elsevier B.V. All rights reserved.