A refrigerator comprising: a cabinet having a storage chamber therein; and a shelf assembly provided in the storage chamber, the shelf assembly being provided with a vertically movable shelf, wherein the shelf assembly includes: a guide member provided in the storage chamber and having inclined guide slots (142, 144) formed at side walls of the guide member, the shelf being supported by the guide member, to be vertically movable; and guide protrusions provided at opposite lateral ends of the shelf and configured to be slidably engaged in the guide slots (142, 144), wherein each guide slot (142, 144) has a bent upper end forming an upper seat (143, 145) to support a corresponding guide protrusion, and the upper seat (143, 145) is formed such that a straight vertical line extending downwards from a center of the upper seat passes through the center of a lower seat of the guide slot (142, 144) and a pair of lever assemblies pivotally provided to the side walls of the guide member and arranged to push the guide protrusions in a rearward direction when the guide protrusions move to the upper seats (143, 145) of the guide slots (142, 144), wherein each of the lever assemblies comprises: a lever guide groove formed at a corresponding one of the side walls of the guide member and having a concave shape; a pivotal pin protruding from the lever guide groove; a lever member pivotally provided to the pivotal pin in the lever guide groove; and an elastic member provided between one side of the lever guide groove and the lever member to push the lever member in the rearward direction. a cabinet having a storage chamber therein; and a shelf assembly provided in the storage chamber, the shelf assembly being provided with a vertically movable shelf, wherein the shelf assembly includes: a guide member provided in the storage chamber and having inclined guide slots (142, 144) formed at side walls of the guide member, the shelf being supported by the guide member, to be vertically movable; and guide protrusions provided at opposite lateral ends of the shelf and configured to be slidably engaged in the guide slots (142, 144), wherein each guide slot (142, 144) has a bent upper end forming an upper seat (143, 145) to support a corresponding guide protrusion, and the upper seat (143, 145) is formed such that a straight vertical line extending downwards from a center of the upper seat passes through the center of a lower seat of the guide slot (142, 144) and a pair of lever assemblies pivotally provided to the side walls of the guide member and arranged to push the guide protrusions in a rearward direction when the guide protrusions move to the upper seats (143, 145) of the guide slots (142, 144), wherein each of the lever assemblies comprises: a lever guide groove formed at a corresponding one of the side walls of the guide member and having a concave shape; a pivotal pin protruding from the lever guide groove; a lever member pivotally provided to the pivotal pin in a guide member provided in the storage chamber and having inclined guide slots (142, 144) formed at side walls of the guide member, the shelf being supported by the guide member, to be vertically movable; and guide protrusions provided at opposite lateral ends of the shelf and configured to be slidably engaged in the guide slots (142, 144), wherein each guide slot (142, 144) has a bent upper end forming an upper seat (143, 145) to support a corresponding guide protrusion, and the upper seat (143, 145) is formed such that a straight vertical line extending downwards from a center of the upper seat passes through the center of a lower seat of the guide slot (142, 144) and a pair of lever assemblies pivotally provided to the side walls of the guide member and arranged to push the guide protrusions in a rearward direction when the guide protrusions move to the upper seats (143, 145) of the guide slots (142, 144), a lever guide groove formed at a corresponding one of the side walls of the guide member and having a concave shape; a pivotal pin protruding from the lever guide groove; a lever member pivotally provided to the pivotal pin in the lever guide groove; and