R&D investment leap is the behavior of an organization to significantly increase or decrease R&D investment in a specific period. Existing literature on R&D investment leap does not pay enough attention to the antecedents. This paper analyzes and tests the knowledge base antecedents of R&D investment leap based on the Punctuated Equilibrium payoff and risk perspective, using a panel data of Chinese listed companies from 2009-2018 as a sample. The results show that technical knowledge base has an opposite effect on R&D investment leap in different directions. Technical diversity and technical complexity have significant positive effects on upward R&D investment leap from exploitation to exploration, technical diversity has significant negative effects on downward R&D investment leap from exploration to exploitation, but technical complexity does not have significant negative effects on downward R&D investment leap. Moreover, environment shock moderate their relationship. When environment shock is advantage, organizations with stronger technical knowledge base are more likely to carry out upward R&D investment; otherwise, organizations with stronger technical knowledge base will slow down the downward R&D investment leap. The results help to enrich and deepen the theoretical study of R&D investment volatility, and have implications for R&D investment decisions in the VUCA environment.