A fuel supply device for gas turbine engine, which supplies fuel to a combustor; said fuel supply device including a fuel injection unit including a pilot burner and a main burner; the fuel supply device further comprising; a pilot fuel passage through which the fuel is supplied to the pilot burner; a main fuel passage through which the fuel is supplied to the main burner; a collecting fuel passage through which the fuel is supplied to the pilot fuel passage and to the main fuel passage; and a fuel divider which divides the fuel supplied from the collecting fuel passage to feed the fuel to the pilot fuel passage and to the main fuel passage; wherein the fuel divider includes: a fuel entrance into which the fuel supplied from the collecting fuel passage is introduced; a pilot port connected to the pilot fuel passage; a main port connected to the main fuel passage; and a movable member which is movable according to a fuel pressure at the fuel entrance; and opens and closes the pilot port and the main port according to a distance of movement of the movable member; wherein when the fuel pressure at the fuel entrance is not higher than a predetermined value, the fuel is supplied only to the pilot fuel passage, wherein, when the fuel pressure at the fuel entrance is higher than the predetermined value, the fuel is supplied to the pilot fuel passage and to the main fuel passage, wherein the pilot port of the fuel divider includes a plurality of pilot ports, characterized in that the main port of the fuel divider includes a plurality of main ports; and in that the movable member is configured close the plurality of pilot ports sequentially, while opening the plurality of main ports sequentially,as the fuel pressure at the fuel entrance increases. a pilot fuel passage through which the fuel is supplied to the pilot burner; a main fuel passage through which the fuel is supplied to the main burner; a collecting fuel passage through which the fuel is supplied to the pilot fuel passage and to the main fuel passage; and a fuel divider which divides the fuel supplied from the collecting fuel passage to feed the fuel to the pilot fuel passage and to the main fuel passage; wherein the fuel divider includes: a fuel entrance into which the fuel supplied from the collecting fuel passage is introduced; a pilot port connected to the pilot fuel passage; a main port connected to the main fuel passage; and a movable member which is movable according to a fuel pressure at the fuel entrance; and opens and closes the pilot port and the main port according to a distance of movement of the movable member; a fuel entrance into which the fuel supplied from the collecting fuel passage is introduced; a pilot port connected to the pilot fuel passage; a main port connected to the main fuel passage; and a movable member which is movable according to a fuel pressure at the fuel entrance; and opens and closes the pilot port and the main port according to a distance of movement of the movable member; wherein when the fuel pressure at the fuel entrance is not higher than a predetermined value, the fuel is supplied only to the pilot fuel passage, wherein, when the fuel pressure at the fuel entrance is higher than the predetermined value, the fuel is supplied to the pilot fuel passage and to the main fuel passage, wherein the pilot port of the fuel divider includes a plurality of pilot ports, characterized in that the main port of the fuel divider includes a plurality of main ports; and in that the movable member is configured close the plurality of pilot ports sequentially, while opening the plurality of main ports sequentially,as the fuel pressure at the fuel entrance increases.