It aims to study the types, characteristics and existing problems of the parking warning devices, and find a way to construct new innovative solution efficiently. The nine-screen approach is used to find new problem-solving ideas, and then the corresponding secondary problem could be solved by the systematic process of product improvement. With application of ideal final result and resource analysis method, the ideality of technical system could be further improved. Design results show that the new solution provide more useful function to customers, while the cost of the product could be greatly reduced. As a highly ideality solution, it can give a positive reference for other product innovation.