A process for controlling the temperature of glass inside a forehearth for the formation of gobs comprises the steps of: determining a set temperature of the glass in the zone No. 1 by effecting a fuzzy inference based on a preset membership function and a preset inference rule of a preset fuzzy set by using two variables, i.e., a deviation between a measured temperature and a set temperature of glass in the spout portion and a timevarying change amount between a temperature measured at a current measurement and a temperature measured at a previous measurement with respect to the glass in the spout portion, as an antecedence; determining a set temperature of the glass in each of zone Nos. 2 and 3 through a fuzzy inference based on a preset membership function and a preset inference rule of a preset fuzzy set through taking two variables, i.e., a deviation amount between a temperature of the glass measured in each of the zone Nos. 2 and 3 and a set temperature of the glass therefor and a time-varying change amount between a temperature measured at a current measurement and a temperature measured at a previous measurement, as an antecedence; and controlling an amount of a combustion gas through each burners by adjusting a set open degree of each cooling valve and a set value of the glass in each of the zone Nos. 1 through 3 based on the set temperatures determined.