The invention provides a security constraint generation schedule planning method based on water and fire coordination. The method comprises the following steps that power grid basic data are acquired, and electricity demands are determined; based on 'just, fair and open' dispatching and energy-saving dispatching, the electric quantity is balanced, and electric power is adjusted; according to the water and fire coordination constraint demand, the constraint condition of a water and fire coordination joint optimization model is determined; an optimization objective is determined; water and fire coordination joint optimization computing is carried out, and the generation schedule is determined. According to the method, based on the running and planning characteristic of a power grid including a large-scale water and electricity access dispatching mechanism, the water and electricity running and water and fire coordination optimizing characteristics are combined, the optimization objective includes the running cost of a thermal power unit and a hydropower unit and a unit output force adjusting penalty function, peak elimination and valley filling are carried out through coordination of the hydropower unit and the thermal power unit, so that the total adjusting amplitude of output force of the units in the system is reduced, and therefore power adjustment losses of the units in the system are reduced.