Started from the requirements of power distribution scheme planning for offshore oil and gas platform commissioning, the topological structure of power network is described with the graph structure, the changes of connectivity relationship of circuit breakers caused by the mutual exclusion relationship are treated with the derivative graphs, and the power distribution scheme is planned with the pathfinding algorithm. The power distribution scheme is verified, the reasonable power supply path is determined, and the power distribution software of offshore oil and gas platform commissioning is developed. The research can provide technical support as required for the related commissioning work of offshore oil and gas platform.