The described technology relates to a needleless syringe for injecting an injection objective substance into an injection target area. The needleless syringe includes a protruding member which is provided movably from a first position to a second position at which 1) a protruding length of a forward end of the protruding member from an end surface of a housing is shorter than a protruding length of the forward end at the first position and 2) the forward end and a discharge port can be brought in contact with the injection target area. The needleless syringe also includes a maintaining mechanism which maintains the protruding member at the first position and a power source circuit which applies a voltage to a driving unit when the protruding member having been maintained at the first position is moved to the second position. Accordingly, the unintended discharge from the syringe is appropriately avoided.
