Disclosed are a combined decision method for power generation plans of multiple power sources, and a storage medium. The multiple power sources comprise a power generation system composed of thermal power, wind power and pumped storage. The combined decision method is: according to power grid requirement information, combined with a power balance analysis result, preferably choosing a starting and stopping state of a thermal power set; establishing an optimization model in which the multiple power sources are coordinated, and carrying out joint optimization for active power outputting of a wind power-thermal power-pumped storage set; and implementing a security check on an active power outputting plan of the multiple power sources, iteratively correcting a starting and stopping plan of the thermal power set, and finally, generating a combined power generation plan of the multiple power sources. The present solution brings wind power prediction data into power balance and arranges the starting and stopping of a thermal power set in advance, so that the effect of peak clipping and valley filling of a pumped storage set can be achieved, and a joint decision of power generation plans of multiple power sources, such as thermal power, wind power and pumped storage, can be realized so as to replace or reduce the power generation capacity of a thermal power set, and thus the consumption and absorption level for clean energy of a power grid can be improved.