The present disclosure relates a shelf support device and a cooking appliance with the same. The shelf support device includes a rail extending in forward and backward directions to locate a front end portion over a rear end portion, including an upper surface portion and a lower surface portion; and a support unit at which a shelf is mounted at an upper portion of the support unit, coupled to the rail to be movable along the movement path formed by each of the upper surface portion and the lower surface portion, and configured to change a position of the shelf in an upward direction when being moved in the forward direction and the position of the shelf in a downward direction when being moved in the backward direction.