A shelf supporting apparatus for supporting a shelf installed in a chamber formed in a body of a cooking appliance, the cooking appliance having a door rotatably installed on the body to open and close the chamber, the shelf supporting apparatus comprising: a pair of fixing frames provided to face each other on opposite sides of the chamber; a pair of supports having a length which is changeable in a frontward-rearward direction, the pair of supports is, respectively, coupled to the pair of fixing frames, wherein the pair of supports is configured to mount the shelf thereon; coupling members provided on the pair of fixing frames and coupling the pair of supports to the pair of fixing frames to be position-changeable in the frontward-rearward direction; and a pair of connecting members that, respectively, connect the pair of supports and the door, having a position which is changed in the frontward-rearward direction in conjunction with a rotation of the door, and changing positions of the pair of supports in the frontward-rearward direction, wherein the pair of connecting members each includes a bracket for installing on the door and a link having a first side coupled to a respective support of the pair of supports and a second side hinge-coupled to the bracket, wherein the link includes a first link, a second link and a third link connected between the first link and the second link, wherein the first link has a first side coupled to the support and a second side that extends downwardly toward a bottom surface of the chamber, wherein the second side of the first link is connected to a first side of the third link, wherein the second link extends from a second side of the third link to the door and is rotatably coupled to the bracket, and wherein the third link extends in a horizontal direction from the second side of the first link extended downwardly to the bottom surface of the chamber in a lateral direction from the side of the chamber to a center of the chamber. a pair of fixing frames provided to face each other on opposite sides of the chamber; a pair of supports having a length which is changeable in a frontward-rearward direction, the pair of supports is, respectively, coupled to the pair of fixing frames, wherein the pair of supports is configured to mount the shelf thereon; coupling members provided on the pair of fixing frames and coupling the pair of supports to the pair of fixing frames to be position-changeable in the frontward-rearward direction; and a pair of connecting members that, respectively, connect the pair of supports and the door, having a position which is changed in the frontward-rearward direction in conjunction with a rotation of the door, and changing positions of the pair of supports in the frontward-rearward direction, wherein the pair of connecting members each includes a bracket for installing on the door and a link having a first side coupled to a respective support of the pair of supports and a second side hinge-coupled to the bracket, wherein the link includes a first link, a second link and a third link connected between the first link and the second link, wherein the first link has a first side coupled to the support and a second side that extends downwardly toward a bottom surface of the chamber, wherein the second side of the first link is connected to a first side of the third link, wherein the second link extends from a second side of the third link to the door and is rotatably coupled to the bracket, and wherein the third link extends in a horizontal direction from the second side of the first link extended downwardly to the bottom surface of the chamber in a lateral direction from the side of the chamber to a center of the chamber.