The invention discloses a weighing sensor and an electronic scale provided with the same. The weighing sensor comprises a flat plate formed into helical shape, including successively a load-supporting portion, a strain portion and a bearing portion from the center to the outer of this plate, with the load-supporting portion situated between and surrounded by the bearing portion and the strain portion; wherein the load-supporting portion and the bearing portion are respectively used to bear the acting force and the reaction force in opposite directions, and a strain gauge is mounted on the strain portion. The electronic scale comprises at least three weighing sensors, wherein the bearing portion of the sensor is mounted on the scale body, the load-supporting portion directly contacts the supporting leg of the scale, which contacts the plane on which the scale is positioned. The present invention has small thickness, simple structure and low manufacturing cost.