Abstract: A foot rest assembly for chairs includes a base frame secured to an underside of a chair and having a first positioning hole defined therein, a mounting member having a foot rest mounted thereon, a linking member, and a positioning member. The linking member includes a first end pivotally connected to the base frame and a second end pivotally connected to the mounting member, and a second positioning hole. A cable is extended through the positioning member and includes a first end secured to the mounting member and a second end. The positioning member further includes a positioning rod having a first end attached to the second end of the cable to move therewith and a second end extended through the first positioning hole.