The invention belongs to the field of biomass foam materials and particularly discloses a paper pulp foam material and a preparation method thereof. The paper pulp foam material is prepared from the following components in parts by weight: 0.5-2.5 parts of paper pulp, 0.005-0.125 part of a surfactant, 0.0005-0.0125 part of cationic polyacrylamide and 97.4-99.5 parts of water. The paper pulp foam material is low in density, high in porosity, green and degradable; the preparation method is abundant in raw material source, simple and feasible in operation, low in cost and environmentally friendly in preparation technology.