The invention discloses a blow-molded member and a manufacturing method thereof. The blow-molded member comprises the following components by weight: 100 parts of high density polyethylene, 72-76 parts of low density polyethylene, 32-38 parts of polyethylene, 4-5 parts of maleic anhydride, 2-4 parts of color masterbatch, and 40-50 parts of crushed materials. The manufacturing method of the blow-molded member comprises the following steps: step one, manufacturing a plastic parison, adding high density polyethylene, low density polyethylene, polyethylene, maleic anhydride, color masterbatch, and crushed materials into clack-matched molds; step two, closing the clack-matched molds on the plastic parison, tightly clamping the clack-matched molds while cutting the plastic parison, heating the clack-matched molds; step three, blowing up the parison through the cold walls of the mold cavity of the clack-matched molds, adjusting opening, and maintaining the pressure during cooling; step four, opening the clack-matched molds, demolding the blown blow-molded member parts; step five, finishing trimming to obtain the blow-molded member finished product. The manufacturing method of the invention reduces the cost, improves the compatibility, and simplifies the structure.