Taking Qingdao Haier as a case study, this paper systematically investigates the impact of its “internal platform and external ecology” business model design in the stage of ecological brand strategy and the matching chain group organization management innovation on the concept, mechanism and method of enterprise cost management. It is found that with a large number of users participating in product definition, the starting point of business model innovation has shifted to the completion stage of a round of value transfer process. The internal organizational structure and external cooperation mechanism in business model design will put forward new requirements for the cost management system at the grass-roots level and the cost management concept at the decision-making level, and promote its continuous optimization. A good cost management system should not only combine cost management with performance evaluation mechanism to give full play to the autonomy and initiative of grass-roots organizations, but also give real-time feedback to the resources and user inputs attached behind the product system, so as to ensure that cost management is highly consistent with the enterprise strategy and business model and become a supporting mechanism for the latter.