The invention relates to black sizing agent with low photosensitivity for a PDP front substrate. The black sizing agent comprises the following components in part by mass: 1-5 parts of azide used as a photosensitive crosslinker, 5-20 parts of non-photosensitive polymer resin, 10-35 parts of glass powder with low melting point, 5-35 parts of black pigment, 10-40 parts of organic solvent, 0.1-1 part of nanometer silver powder, 0-1 part of coupling agent and 0-1 part of flatting agent, wherein the azide is used as a photosensitive crosslinker; and the black pigment is a composite which is prepared by the following methods of: ball-milling and mixing two or more than two of Co3O4, Fe2O3, Ni2O3 and MnO2 uniformly and proportionally; placing the materials into a high-aluminum crucible to sinterfor 2 to 4 hours at the temperature of between 1,200+/-50 DEG C; pouring the materials quickly into cold water to quench; ball-milling the materials by a planetary ball mill; adding a certain amount of Bi2O3 into the materials to mix uniformly after the materials are dried; then performing secondary sintering on the mixture for 1 to 3 hours at the temperature of between 1,200+/-50 DEG C; and ball-milling the mixture to 0.8 to 3 microns.