There is provided a link mechanism for a chair that is a link mechanism that is used at a chair, the link mechanism for a chair having: a first link whose one end is connected to a bottom surface of a link that supports a seat surface portion of the chair; a second link whose one end is connected to another end of the first link; a first joint portion rotatably connecting the first link and the second link; a second joint portion provided at another end of the second link; and a first elastic resistance unit imparting elasticity in a rotating direction to the second joint portion.