A customer requirements motivated flexible platform functional module identification method is proposed to integrate requirement analysis，functional modeling，modular identification and module classification in the conceptual design stage of flexible product platform，based on the model of top-down mapping and bottom-up feedback. Because of the fuzzy characteristic of customer requirements，a fuzzy Kano model is introduced to classify the information of needs. A requirements’ hierarchical expanding method is presented to construct the product function model represented with the material flow，energy flow and signal flow. Three heuristic rules are used to identify functional modules，and the basic，flexible and individualized modular types are set up according to the satisfied requirements’ classification. Thus，the complex mathematical computation for modular planning can be avoided，and customer requirement analysis is merged with the modular planning process. The effectiveness of the method is illustrated through the functional module planning for hydraulic support platform.