To provide a method for producing a fluorescent material for a scintillator having improved light emission intensity.

The method for producing the fluorescent material in a garnet structure using Ce as a light-emitting element, and containing Gd, Ga, Al and O includes a temperature-raising step of raising the temperature of a molded article, a sintering step of sintering the molded article at a temperature within the range of 1,300-1,700°C, and a temperature-decreasing step of decreasing the temperature of the sintered body after the sintering. The temperature-decreasing step is controlled so that the decrease of the temperature is started at a temperature-decreasing rate of 75-300°C/h. Preferably, the temperature-decreasing step is carried out by decreasing the temperature at the first temperature-decreasing rate of 75-300°C/h, and further decreasing the temperature by changing the temperature-decreasing rate to the second temperature-decreasing rate more rapid than the first temperature-decreasing rate in the midway of the decrease of the temperature.