The technological gap is the key reason why China's core technology is difficult to break through. From a macro perspective, economic policies and technological policies have a certain impact on technological change. From the perspective of micro-enterprises, the sustained profit growth obtained from core technological breakthroughs determines the investment motivation for technological research and development. Using the product quality model and learning from the Lotka-Volterra theory, the System-Dynamics model was constructed from key variables such as technological gap and substitution flexibility. The study found that a looser technological competition environment can bring higher R&D output efficiency, and the initial value of the technological gap is lower. Downsizing can bring greater incentives for R&D investment, and the increase in substitution elasticity is not conducive to the increase in the output efficiency of R&D inputs.