A fuel injector that is supplied with compressed air from an upstream side, the fuel injector comprising: a pilot fuel injection portion including a pilot fuel supply block and a tubular pilot shroud, the pilot shroud being arranged at a radially outer side of the pilot fuel supply block and projecting to a downstream side beyond the pilot fuel supply block; a main fuel injection portion including a main air passage in which a pre-mixed gas is generated, the main fuel injection portion being arranged so as to surround the pilot fuel injection portion from an outer side in a radial direction; and an intermediate air passage arranged between the pilot fuel injection portion and the main fuel injection portion, wherein: the pilot shroud includes a throat located at the downstream side of the pilot fuel supply block and a flame holding portion surrounding flame located at the downstream side of the throat, the flame holding portion having a shape that increases in diameter toward the downstream side; wherein an air injection slit that is open toward the downstream side and the radially outer side is formed at the flame holding portion, characterized in that the air injection slit is configured to inject the compressed air of the intermediate air passage in a direction along an inner peripheral surface of the flame holding portion such that the compressed air covers the inner peripheral surface over an entire periphery. a pilot fuel injection portion including a pilot fuel supply block and a tubular pilot shroud, the pilot shroud being arranged at a radially outer side of the pilot fuel supply block and projecting to a downstream side beyond the pilot fuel supply block; a main fuel injection portion including a main air passage in which a pre-mixed gas is generated, the main fuel injection portion being arranged so as to surround the pilot fuel injection portion from an outer side in a radial direction; and an intermediate air passage arranged between the pilot fuel injection portion and the main fuel injection portion, wherein: the pilot shroud includes a throat located at the downstream side of the pilot fuel supply block and a flame holding portion surrounding flame located at the downstream side of the throat, the flame holding portion having a shape that increases in diameter toward the downstream side; wherein an air injection slit that is open toward the downstream side and the radially outer side is formed at the flame holding portion, characterized in that the air injection slit is configured to inject the compressed air of the intermediate air passage in a direction along an inner peripheral surface of the flame holding portion such that the compressed air covers the inner peripheral surface over an entire periphery. a throat located at the downstream side of the pilot fuel supply block and a flame holding portion surrounding flame located at the downstream side of the throat, the flame holding portion having a shape that increases in diameter toward the downstream side; wherein an air injection slit that is open toward the downstream side and the radially outer side is formed at the flame holding portion, characterized in that the air injection slit is configured to inject the compressed air of the intermediate air passage in a direction along an inner peripheral surface of the flame holding portion such that the compressed air covers the inner peripheral surface over an entire periphery.