The invention discloses a porous LaCr oxide-carbon composite material and a synthesis method thereof. The porous LaCr oxide-carbon composite material comprises LaCr<2-x>O<3> and carbon, wherein the LaCr<2-x>O<3> and the carbon are uniformly mixed to form a La Cr oxide-carbon composite layer, holes are formed in the La Cr oxide-carbon composite layer, in the porous La Cr oxide-carbon composite material, the carbon accounts for 70-90wt%, x is more than or equal to 0.5 but less than or equal to 2, the holes are 200-400 nanometers, and the porous LaCr oxide-carbon composite material is prepared by a template impregnated sintering method. The porous La Cr oxide-carbon composite material can be used for providing larger specific area and is provided with more active sites, so that higher catalytic performance is obtained.