The present invention discloses an annular ring for preventing water from penetrating into electronic products including: an annular ring body, the cross section of the annular ring body having a shape with a concave notch; wherein the notch sleeves a protruded edge on a component in an electronic product. In another aspect, the present invention discloses an annular ring for preventing water from penetrating into electronic products including: an annular ring body, the cross section of the annular ring body is slice shaped; wherein the annular ring body is disposed at the lateral side of a protruded edge on a component in an electronic product, such that the lateral surface of the annular ring body fits the lateral surface of the protruded edge.