A needleless syringe comprises an enclosing unit for an injection objective substance, a pressurizing unit for the injection objective substance, a discharge unit having a flow passage for allowing the injection objective substance to flow therethrough so that the injection objective substance is discharged from an open end of the flow passage to an injection target area, the open end being formed so that an area thereof is smaller than a flow passage area of the enclosing unit, and a minute pore unit including a minute pore having a flow passage area smaller than the area of the open end of the discharge unit and which is arranged on an outer side of the open end so that the injection objective substance discharged from the open end passes through the minute pore and arrives at a side of the injection target area.