A fuel supply control device for a gas turbine that is configured to control a fuel supply pump on the basis of a front-rear differential pressure across a metering valve for a fuel supply amount, which is detected by a differential pressure gauge, using parallel flow passages of an orifice and a pressurizing valve as the metering valve, the fuel supply control device comprising: a first control amount generation unit that is configured to generate a first control amount on the basis of the front-rear differential pressure; and a second control amount generation unit (8b, 8c, 8d) that is configured to generate a second control amount on the basis of a rotation speed of the fuel supply pump, characterized in that the fuel supply control device further comprises: a control amount selection unit (8e, 8f) that is configured to alternatively select the first control amount or the second control amount on the basis of the rotation speed and to output the selected control amount; a subtractor that is configured to calculate a deviation of an output of the control amount selection unit (8e, 8f) from a control target value and to output the deviation; and a control calculation unit that is configured to calculate an operation amount of the fuel supply pump on the basis of an output of the subtractor, wherein the control amount selection unit (8e, 8f) is configured to select the first control amount in a case where the rotation speed is equal to or lower than a predetermined threshold and to select the second control amount instead of the first control amount in a case where the rotation speed exceeds the threshold. a first control amount generation unit that is configured to generate a first control amount on the basis of the front-rear differential pressure; and a second control amount generation unit (8b, 8c, 8d) that is configured to generate a second control amount on the basis of a rotation speed of the fuel supply pump, characterized in that the fuel supply control device further comprises: a control amount selection unit (8e, 8f) that is configured to alternatively select the first control amount or the second control amount on the basis of the rotation speed and to output the selected control amount; a subtractor that is configured to calculate a deviation of an output of the control amount selection unit (8e, 8f) from a control target value and to output the deviation; and a control calculation unit that is configured to calculate an operation amount of the fuel supply pump on the basis of an output of the subtractor, wherein the control amount selection unit (8e, 8f) is configured to select the first control amount in a case where the rotation speed is equal to or lower than a predetermined threshold and to select the second control amount instead of the first control amount in a case where the rotation speed exceeds the threshold. a control amount selection unit (8e, 8f) that is configured to alternatively select the first control amount or the second control amount on the basis of the rotation speed and to output the selected control amount; a subtractor that is configured to calculate a deviation of an output of the control amount selection unit (8e, 8f) from a control target value and to output the deviation; and a control calculation unit that is configured to calculate an operation amount of the fuel supply pump on the basis of an output of the subtractor, wherein the control amount selection unit (8e, 8f) is configured to select the first control amount in a case where the rotation speed is equal to or lower than a predetermined threshold and to select the second control amount instead of the first control amount in a case where the rotation speed exceeds the threshold.