Aiming at the problem of equilibrium and dynamic development of electricity market，a bi-level model of non-cooperative game is firstly established in this paper，which can directly reflect the changes of market equilibrium interests and bidding behavior. Then，an improved firefly algorithm is used to solve this model and compared with the classical firefly algorithm to verify its superiority. Finally，the bi-level equilibrium model is simulated and analyzed from the perspectives of load change，bidding strategy adjustment，price difference contract and cooperative behavior，and the internal relationship between different factors and dynamic development of market equilibrium is obtained，which will provide theoretical reference for guiding market equilibrium.