This paper constructs a two-sector DSGE model, and considers the general law of innovation diffusion (" s-type diffusion ") and the unique role of enterprise green technology innovation diffusion (energy saving and emission reduction). Based on the prediction of population aging, the response of fluctuating economic system with the diffusion of enterprise green technology innovation is simulated. The results show that economic variables have different response paths to the fluctuations of the diffusion of green technology innovation, and the response of capital stock is hysteresis. The "carry-over effect" appears in the response of relevant economic variables headed by the rate of return on capital to positive shocks. Finally, this paper argues that the government should take measures to stabilize the expectations of market participants and adopt the pre-adjustment mechanism in the capital market.