The invention discloses a mixed integer convex programming method for optimal power distribution of AC/DC parallel transmission channels, based on the active power generation dispatching plan of the whole grid generator set and the active power transmission plan of the DC transmission line, by means of processing methods of cone relaxation transformation and large M method equivalence, the objective function and constraint conditions with high nonlinearity are subjected to convexification processing, the established optimization model is transformed into a mixed integer convex programming model which is easy to solve, the obtained optimal power allocation scheme of AC/DC transmission channel can effectively reduce the loss of AC and DC transmission channels, obvious economic benefits are achieved, and the mathematical optimization of the solution is ensured, and the solving efficiency of optimization calculation is improved, so as to achieve the operation economy of AC/DC interconnected power network.