The invention relates to a power transmission stream optimization method involving power transmission paths. The method includes the following steps that (1), a network model is constructed; (2), an electric energy exchange transmitter and an electric energy exchange receiver are set; (3), the physical power transmission paths are all traversed; (4), optimization parameters are set; (5), a power transaction stream optimization model is established; (6), optimization calculation is performed. On the basis of traversing all the power transmission paths, combined optimization is performed; through a linear programming method, transaction stream optimization is achieved, a complex non-linear path optimization problem is transformed into the linear problem, and therefore the practical level of power transaction stream optimization is easily increased.