An air-assist fuel injection nozzle has an externally actuated needle plunger journaled for axial movement in the cylinder provided in a nozzle body. The needle plunger tip contains a central blind bore which communicates with discharge passages and with a supply passage, the latter, when the needle plunger is in a raised position, communicate with a valve controlled supply passage to receive a metered quantity of liquid fuel. Upon downward movement of the needle plunger a predetermined axial extent, the discharge passages come into flow communication with corresponding discharge orifices provided in the nozzle body. A central pedestal or pin upstanding from the lower closed end of the nozzle body substantially fills the blind bore in the needle plunger during the injection process in order to minimize the total clearance volume.