The present disclosure relates to a needleless injector including a cap, an injection system, a body, and a compression spring. The body is mounted to slide upwards in relation to the cap along an injection axis between a rest position and an injection position. The compression spring is axially intercalated along the injection axis between the body and the cap to compress the skin tissue of the user when the nozzle is applied to the skin. The compression spring is a frustroconical helical spring that extends along the injection axis and includes a plurality of turns designed to nest axially one inside the other.
