To discover the knowledge used to trigger design inspiration in complex data, a new method, namely the method of acquiring knowledge aimed to trigger design inspiration, was proposed. According to the ways of triggering design inspiration, it firstly explains the diversity data used for stimulating inspiration, and then analyzes diversity knowledge used to aid innovation design, the process model of discovering knowledge for triggering design inspiration is constructed by means of various resources. The concerned knowledge is discovered and used for supporting product innovation in next stage. Finally, the method is demonstrated by creative design of product. The obtained result proves the validity of this method.