A MEMS element, comprising: a base constituted with a silicon substrate; a device layer electrically insulated from the base; a fixed electrode (141, 142) and a movable electrode (131, 132) formed in the device layer; the fixed electrode (141, 142) having a plurality of fixed comb teeth (141a, 142a), a fixed electrode pad and a support fastening portion; and the movable electrode (131, 132) having a plurality of movable comb teeth (131a, 132a) which are interdigitated with the fixed comb teeth (141a, 142a), wherein: the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth (141a, 142a); and the base comprises an opening, wherein the fixed electrode (141, 142) and the movable electrode are at least in part disposed over the opening; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion, wherein a fastening portion is disposed at the end of the projecting portion; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base, which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad, is removed, forming a gap between the projecting portion and the comb tooth linking portion. a base constituted with a silicon substrate; a device layer electrically insulated from the base; a fixed electrode (141, 142) and a movable electrode (131, 132) formed in the device layer; the fixed electrode (141, 142) having a plurality of fixed comb teeth (141a, 142a), a fixed electrode pad and a support fastening portion; and the movable electrode (131, 132) having a plurality of movable comb teeth (131a, 132a) which are interdigitated with the fixed comb teeth (141a, 142a), wherein: the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth (141a, 142a); and the base comprises an opening, wherein the fixed electrode (141, 142) and the movable electrode are at least in part disposed over the opening; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion, wherein a fastening portion is disposed at the end of the projecting portion; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base, which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad, is removed, forming a gap between the projecting portion and the comb tooth linking portion. the support fastening portion includes a comb tooth linking portion that connects the plurality of fixed comb teeth (141a, 142a); and the base comprises an opening, wherein the fixed electrode (141, 142) and the movable electrode are at least in part disposed over the opening; characterised in that the base comprises a projecting portion which projects from an edge of the opening and extends along the comb tooth linking portion, wherein a fastening portion is disposed at the end of the projecting portion; wherein the end of the comb tooth linking portion is fixed to the fastening portion at the end of the projecting portion and a portion of the base, which would face opposite at least part of the comb tooth linking portion between the fastening portion and the fixed electrode pad, is removed, forming a gap between the projecting portion and the comb tooth linking portion.