The invention discloses a partition power grid bus load prediction system based on weather information. Real-time weather information and prediction weather information are used in the system, load prediction of all buses of converting stations of 500 kV and 220 kV is achieved, and recognition of power grid partition and partition load prediction are achieved. A prediction algorithm used by the system comprises a classical algorithm and an intelligent prediction algorithm, the classical algorithm comprises unary linear regression, quadratic polynomial regression, self-adaptation index prediction, index prediction, increasing rate prediction, nonhomogeneous index prediction, a B. Compertz model and a logistic model, the intelligent prediction algorithm comprises an optimized BP neural network algorithm and an optimized particle swarm algorithm, and the system selects a prediction algorithm in a preferential mode during a prediction process. The system is a day-ahead bus load prediction system, bus load and partition load of each time interval from morrow to multiple days in future are predicted, and prediction content is active load of 96 points of a predicted day.