The invention discloses water-based middle coating high in stone-chip resistance. The water-based middle coating is prepared from, by weight, 2-10 parts of oil-free saturated polyester, 15-35 parts ofmodified alkyd resin, 15-35 parts of water-based polyester resin, 2-10 parts of mixed etherified melamine resin, 2-10 parts of methylated amino resin, 1-5 parts of blocked isocyanate, 2-10 parts of polyurethane resin, 10.4-78 parts of pigment and filler, 0.6-21.5 parts of pH regulating agent, 2.61-9.3 parts of additive and 11.2-37 parts of solvent. The coating film gloss of the water-based middlecoating high in stone-chip resistance is effectively controlled to be about 75, and the gloss of the original formula is up to 85; the stone-chip resistant effect of original middle coating is judgedas Class 5 according to the Great Wall standards, and the original middle has the phenomenon that a steel plate is exposed; the stone-chip resistant effect of the water-based middle coating high in stone-chip resistance can reach Class 7, and the phenomenon that the steel plate is exposed does not occur.