A spray ionization device , comprising: a first tube including a first channel through which a liquid can flow, the first tube including a first outlet for ejecting the liquid at one end; a second tube surrounding the first tube ; and a third tube surrounding the second tube with a gap, and having a second channel through which gas can flow, the third tube having a second outlet at the one end, in which the second channel is defined by an outer circumferential surface of the second tube and an inner circumferential surface of the third tube , wherein a tip of the second tube is formed more to an opposite end side than the first outlet , and the second outlet is disposed at the same position in an axial direction as the first outlet or more downstream than the first outlet , wherein an opening diameter of the second outlet is formed to be smaller than a diameter of the outer circumferential surface of the second tube , wherein the third tube has at least a tip including the second outlet consisting of an electrically conductive material as an electrode , and capable of applying an electric field to droplets ejected from the first outlet by a power source connected to the electrode to eject electrically charged droplets from the second outlet , wherein the inner circumferential surface of the third tube progressively decreases in diameter towards the second outlet , wherein the second channel has a constriction portion formed by the inner circumferential surface of the third tube and the tip of the second tube , and characterized in that a channel area of the second channel defined on a plane perpendicular to a central axis progressively decreases from the opposite end to the constriction portion . a first tube including a first channel through which a liquid can flow, the first tube including a first outlet for ejecting the liquid at one end; a second tube surrounding the first tube ; and a third tube surrounding the second tube with a gap, and having a second channel through which gas can flow, the third tube having a second outlet at the one end, in which the second channel is defined by an outer circumferential surface of the second tube and an inner circumferential surface of the third tube , wherein a tip of the second tube is formed more to an opposite end side than the first outlet , and the second outlet is disposed at the same position in an axial direction as the first outlet or more downstream than the first outlet , wherein an opening diameter of the second outlet is formed to be smaller than a diameter of the outer circumferential surface of the second tube , wherein the third tube has at least a tip including the second outlet consisting of an electrically conductive material as an electrode , and capable of applying an electric field to droplets ejected from the first outlet by a power source connected to the electrode to eject electrically charged droplets from the second outlet , wherein the inner circumferential surface of the third tube progressively decreases in diameter towards the second outlet , wherein the second channel has a constriction portion formed by the inner circumferential surface of the third tube and the tip of the second tube , and characterized in that a channel area of the second channel defined on a plane perpendicular to a central axis progressively decreases from the opposite end to the constriction portion . <EOS>