The work aims to drive the iterative updating of kitchen appliances through innovative design methods, explore the application process of Kano-AHP-QFD in the double diamond model, and accurately focus on the real needs of users. The research was guided by the four stages of the double diamond model. In the problem discovery stage, PEST analysis was used to identify macro design opportunities, and relevant user needs were collected through various methods such as online comment mining, user interviews, and surveys. In the problem definition stage, the Kano model was used to categorize need attributes and AHP was employed to calculate need weights. In the design development stage, QFD was used to translate high-weight needs into product technical features and determine their hierarchical weights. In the design implementation stage, the technical features at each level were transformed into specific design proposals. To address issues such as poor comfort and inadequate space utilization in kitchen spaces, a refrigerator design with integrated air conditioning was proposed. To validate the effectiveness of the solution, a Likert scale was used for evaluation. Finally, the solution was transformed into a utility model patent to further verify its innovation and feasibility. The combination of the double diamond model and Kano-AHP-QFD can effectively guide the innovative design of kitchen appliances, thereby enhancing the specific application process of the double diamond model in the field of product design.