A snap button connector in which a male connector portion and a female connector portion are fitted with each other in a fitting direction, wherein the male connector portion includes: - a male connector body having a first base portion and a convex portion projecting from a front surface of the first base portion in the fitting direction; - a plurality of first electrodes arranged in a circumferential direction of the convex portion as being insulated from one another and each extending to a rear surface of the first base portion; and - one or more positioning keys disposed on the front surface of the first base portion, projecting in the fitting direction, wherein the female connector portion includes: - a female connector body having a second base portion and a concave portion forming a recess in the fitting direction on a front surface of the second base portion; - a plurality of second electrodes arranged in a circumferential direction of the concave portion as being insulated from one another and each extending to a rear surface of the second base portion; and - one or more keys-to-be-positioned, which are openings, disposed on the front surface of the second base portion, and wherein, when the male connector portion is fitted with the female connector portion, the convex portion is fitted with the concave portion and the positioning keys are inserted into the keys-to-be-positioned, whereby the plurality of first electrodes are aligned with and electrically connected to the plurality of second electrodes, wherein the convex portion of the male connector portion has, at a tip end thereof in the fitting direction, an overhanging portion overhanging in a radial direction farther away from a root portion that is connected to the front surface of the first base portion, wherein the concave portion of the female connector portion is surrounded by a wall portion extending from the front surface of the second base portion in the fitting direction and is provided with a projecting portion formed on the wall portion and projecting in a radial direction toward a center of the concave portion, wherein, when the male connector portion is fitted with the female connector portion, the projecting portion of the concave portion is in elastic contact with the convex portion while being located between the root portion and the overhanging portion of the convex portion, wherein the plurality of first electrodes each extend from an outer periphery of the convex portion through the front surface of the first base portion and an outer edge of the first base portion to reach the rear surface of the first base portion, wherein the second base portion has a through-hole inside the concave portion, and wherein the plurality of second electrodes each extend from an inner surface of the wall portion of the concave portion through the through-hole to reach the rear surface of the second base portion. - a male connector body having a first base portion and a convex portion projecting from a front surface of the first base portion in the fitting direction; - a plurality of first electrodes arranged in a circumferential direction of the convex portion as being insulated from one another and each extending to a rear surface of the first base portion; and - one or more positioning keys disposed on the front surface of the first base portion, projecting in the fitting direction, - a female connector body having a second base portion and a concave portion forming a recess in the fitting direction on a front surface of the second base portion; - a plurality of second electrodes arranged in a circumferential direction of the concave portion as being insulated from one another and each extending to a rear surface of the second base portion; and - one or more keys-to-be-positioned, which are openings, disposed on the front surface of the second base portion, and