Hoist crane, which is usually installed at a factory ceiling, is an equipment to effectively upload and move very heavy weight parts in various industries. If a strength of the crane were not enough to support the heavy weight, either high deformation or large distortion at the hoist components would occur during the operation of the crane. For the sake of safety, the inside supporting plates in a horizontal beam (commonly called a girder) of the hoist crane must be sufficiently thickened. It is uneconomic to apply the thick plates in the girder and the crane is too much heavy. To solve this problem, the shape and the thick of the girder was optimized by finite element analysis based on considering both of the safety and the economics in the hoist crane.