The invention relates to the field of hydropower station optimization scheduling running and discloses a situational analysis based large, medium and small hydropower station short-period largest consumable electric quantity coordination optimization scheduling method. The method comprises establishing output situations and probability distribution of small hydropower stations of all sub-areas through a fuzzy clustering method, performing calculation by combining heuristic search and a correlation search method, and for abandoned electricity expectation value which cannot be consumed by the sub-areas, introducing a restraint step-by-step relaxing strategy to further improve the hydropower station consumption capacity by using the good regulation capacity of large and medium hydropower stations. The method has the advantages that large hydropower station output flexibility can be enhanced to meet the small hydropower station sending requirement, and accordingly, the hydropower station consumption capacity is improved, impact of small hydropower stations on the main network is reduced, large and small hydropower station short-period coordination optimization scheduling under the outer sending output limit of the sub-areas is achieved, and good reference values are provided for improving of the clean energy utilization rate of rich hydropower station regions and the deepening of energy conservation and emission reduction.