A seismic damper includes upper and lower brackets, and a link mechanism. The upper bracket is formed with an upper hole. The lower bracket is formed with lower and intermediate holes. The link mechanism includes a support link, and first, second, and third pivot joints. The support link has first and second ends, each of which is formed with a through-hole, and an intermediate portion, which is formed with a through-hole. The first pivot joint extends through the upper hole in the upper bracket and the through-hole in the first end of the support link. The second pivot joint extends through the lower hole in the lower bracket and the through-hole in the second end of the support link. The third pivot joint extends through the intermediate hole in the lower bracket and the through-hole in the intermediate portion of the support link.