The expansion of the design field and the complication of design issues require new design knowledge, and design research in practice is the main way of new design knowledge production. This study conducts multi-level research on the knowledge production phenomenon in practice-based design research, establishes new design research modes from the perspective of knowledge production, and explores the corresponding design research project management strategy. The main research purpose of this study are: discovering the mechanism for new knowledge production in practice-based design research defining the classification of practice-based design research modes based on knowledge production characteristics; and offering design research strategy recommendations from knowledge production perspective. Aiming at the above research issues, from the perspective of knowledge production, the theory of new production of knowledge and the Legitimation Code Theory are applied. Three theoretical models are proposed, which are knowledge production cross-border model, knowledge production heterogeneity model and knowledge production process model. Then, the three theoretical models are applied to analyse six design research cases. The conclusion discovered the knowledge production mechanism in practice-based design research, that is, the purpose of research determines the cross-border mode of knowledge production; the quality of design research conclusions is related to the heterogeneity of knowledge production; the knowledge production process contains multiple iterations of semantic waves, and produces powerful knowledge and contextual knowledge. Based on this discovery, four practice-based design research modes are proposed.