The research of compete price mechanism always is the difficulty to design power market. This paper uses the Swarm simulation as a research technique, to carry on the comparative analysis in two kinds of compete price mechanism. Through the simulation, it discovers some phenomena in MCP (Market clearing price) and PAB (Pay-as-Bid) under the mechanism. In the electricity generation business and gaming process, the price in PAB mechanism is lower than it in MCP mechanism. After electricity generation business gambling achieved market equilibrium, the price under the MAC mechanism is lower than it in PAB mechanism. After the PAB mechanism achieved market equilibrium, the electric quantity and the deal price volatility margin is smaller than the MCP mechanism. Unconscious collusion in competition gambling process also is one of cause which generator implement cause market power in PAB and MCP mechanism.