A new method of transmission fixed cost allocation is presented in an electricity market coexisting with different transaction modes such as pool transaction mode, bilateral transaction mode and multilateral transaction mode. The method is on the basis of the current separation. 针对在多种交易模式(联营体交易、双边交易、多边交易)共存的电力市场中,如何公平合理地分摊输电网的固定成本这一问题,提出了一种新的固定成本分摊方法。