Boiler combustion control system and boiler combustion control method

Disclosed is a boiler combustion control system that outputs a fuel correction coefficient for correcting a load demand amount after feedback correction. This system comprises: a fuel correction coefficient computation unit that calculates a fuel correction coefficient on the basis of a ratio between load demand amounts before and after feedback correction, and an initial value and a fine adjustment function that define an initial value of a relationship between the load demand amount and a fuel supply amount; and a reference curve correction unit that outputs a reference curve correction coefficient for correcting the initial value and the fine adjustment function. The reference curve correction unit includes: a deviation determination unit that calculates the deviation between a measured main steam pressure and a setting main steam pressure; a period determination unit that acquires a period related to the fluctuation of the deviation; an amplitude determination unit that acquires amplitude; a reference curve correction coefficient output unit that calculates and outputs the reference curve correction coefficient on the basis of a reference curve correction function; and a reference curve correction determination unit that corrects the reference curve correction function in cases where the combination of the period and the amplitude satisfies a predetermined condition.