A vane rotary compressor includes a roller rotatably supported in a cylinder and including a plurality of vane slots formed along a circumferential direction with back pressure chambers formed at one end of each of the vane slots A plurality of vanes are slidably supported in the vane slots protruding toward an inner circumferential surface of the cylinder. A compression space formed by the vanes between the roller and the cylinder includes an inlet port and an outlet port formed at both sides of a contact point between the roller and the cylinder. A vane positioned between the inlet port and the outlet port is configured such that a front gap between a front surface of the vane and the inner circumferential surface of the cylinder is smaller than a rear gap between a rear surface of the vane and an inner surface of the back pressure chamber.