PROBLEM TO BE SOLVED: To provide a fuel injection valve with enhanced uniformity of a swirl flow in the circumferential direction.SOLUTION: A fuel injection valve includes: a swirling chamber 22a having an inner wall surface that forms a helical curve; and a passage 21a for swirling that directs fuel into the swirling chamber. The valve is formed such that the center of a circle as the basis of the helical curve and the center of a fuel injection hole 23a open in the swirling chamber 22a align with one another. The joint between the passage 21a for swirling and the inner circumferential wall on the downstream side of the swirling chamber at which both walls intersect is positioned between a line segment from the center of the fuel injection hole 23a to a point at which the curvature of the swirling chamber shape starts to change; and a tangential line of the side wall of the fuel injection hole 23a drawn so as to be in parallel to the line segment. The shape of the swirling chamber is defined by a logarithmic spiral calculated from flow rate conservation formulas in the radial direction and in the circumferential direction of the swirling chamber 22a. The logarithmic spiral is a function of the width of the passage 21a for swirling that directs fuel into the swirling chamber 22a and the distance from the center of the fuel injection hole to the side wall of the passage for swirling.
