The invention discloses a lightweight design method for a drum device of anchor and mooring equipment. The drum device comprises a drum body, a drum shaft, a right side flange, a mesh tooth block, a middle flange, a left side flange, a hub and the like. The design method comprises steps as follows: key parameters of the drum device are extracted, and a three-dimensional parameterized model is established; a virtual prototype of the complete machine is constructed, a mooring rope retracting and releasing process of the drum device of the anchor and mooring equipment is simulated and analyzed according to dynamics simulation, and required load is extracted; parts of the drum device are subjected to finite element analysis; feasibility of optimization measures and computational formulae is theoretically analyzed, the model is optimized, and the drum device, with the best structural size, of the anchor and mooring equipment is determined. According to the method, a conventional extensive type experience design is changed, scientific part strength computation and optimization design is performed with the method combining theoretical analysis, virtual prototype simulation and finite element analysis, so that the technical indexes such as performance, weight and the like of the drum device of the anchor and mooring equipment meet the international advanced level.