PT. XYZ is a company engaged in manufacturing that produces cargo boxes, flatbeds, and other types of equipment for transportation. Warehouse PT. XYZ uses a randomized storage policy. Frequently PT. XYZ was unable to reach its production capacity target because the workers were waiting to arrive at the materials. This material shortage occurs because the raw material warehouse is not optimally used, so there is little material storage space. The space for workers to walk becomes narrow because many raw materials are placed on the floor. Finding raw materials is long because workers have to unload the boxes first due to random placement and there is no name on the box. The proposed layout uses the Class-Based Storage method and is validated using ProModel and FlexSim. Validation with ProModel shows that the transfer time of raw materials is 6.33 minutes faster or more efficient in transferring raw materials increases by 16% from the initial layout. Validation with FlexSim shows that the total output increases by 202 units or 11.60%. The best-proposed layout results obtained with a total distance transfer of raw materials of 39698.39m or the efficiency of transfer raw materials increased by 38.34% and the total cost of material handling is more efficient by IDR 63,052,221 or costs decreased by 29.08%.