In order to develop a new lightweight enclosure structure with an excellent fireproof and bearing performance, and to replace the traditional stiffened fire enclosure bulkheads in the superstructure area, a design method of light fireproof enclosure bulkheads for cruise ship based on the topography optimization technology was proposed. The location and numbers of corrugated beads in lightweight wall designed by this method were generated according to the requirements of load bearing capacity and manufacturing process, and this method overcomes the disadvantages that the location and numbers of beads in the design of conventional corrugated wall have to be determined in advance. Aimed at the specified design regions, the lightweight of cruise fireproof enclosure bulkheads (CFEB) structure was taken as the objective function while the stress in the weld zone, the stress in the nonweld zone, and the first-order buckling factor of CFEB were taken as constraints. Then, the topography design models of CFEB were established and solved. Feasible configurations were obtained by topography optimization, and the final configurations of CFEB were formed by secondary design. The mechanical properties of the final configurations were compared with the traditional stiffened fireproof bulkheads. It is concluded that the new CFEB has advantages of lightweight and good strength compared with the traditional stiffened fireproof bulkheads.