A refrigerator comprising: a cabinet having a storage chamber; and a shelf assembly at the storage chamber, wherein the shelf assembly includes: a pair of guides respectively provided at opposite inner side walls of the storage chamber; rotating members rotatably connected to front and rear sides of the guides, respectively; and a shelf rotatably connected to the rotating members, the shelf arranged to be vertically movable, characterized in that each respective guide of the pair of guides includes: rotating gears (630, 632) provided at the front and rear sides of the respective guide and each configured to rotate in correspondence with a corresponding one of the rotating members; rack gears (640, 642) provided at the front and rear sides of the respective guide and each configured to link to the respective rotating gear (630, 632); a body to support the rotating gears (630, 632) and the rack gears (640, 642), a protrusion (610, 612) being provided at the body; and a linkage to connect the front rack gear and the rear rack gear, the linkage having a guide groove (662, 664) guided by the protrusion (610, 612). a cabinet having a storage chamber; and a shelf assembly at the storage chamber, wherein the shelf assembly includes: a pair of guides respectively provided at opposite inner side walls of the storage chamber; rotating members rotatably connected to front and rear sides of the guides, respectively; and a shelf rotatably connected to the rotating members, the shelf arranged to be vertically movable, characterized in that each respective guide of the pair of guides includes: rotating gears (630, 632) provided at the front and rear sides of the respective guide and each configured to rotate in correspondence with a corresponding one of the rotating members; rack gears (640, 642) provided at the front and rear sides of the respective guide and each configured to link to the respective rotating gear (630, 632); a body to support the rotating gears (630, 632) and the rack gears (640, 642), a protrusion (610, 612) being provided at the body; and a linkage to connect the front rack gear and the rear rack gear, the linkage having a guide groove (662, 664) guided by the protrusion (610, 612). a pair of guides respectively provided at opposite inner side walls of the storage chamber; rotating members rotatably connected to front and rear sides of the guides, respectively; and a shelf rotatably connected to the rotating members, the shelf arranged to be vertically movable, characterized in that each respective guide of the pair of guides includes: rotating gears (630, 632) provided at the front and rear sides of the respective guide and each configured to rotate in correspondence with a corresponding one of the rotating members; rack gears (640, 642) provided at the front and rear sides of the respective guide and each configured to link to the respective rotating gear (630, 632); a body to support the rotating gears (630, 632) and the rack gears (640, 642), a protrusion (610, 612) being provided at the body; and a linkage to connect the front rack gear and the rear rack gear, the linkage having a guide groove (662, 664) guided by the protrusion (610, 612). rotating gears (630, 632) provided at the front and rear sides of the respective guide and each configured to rotate in correspondence with a corresponding one of the rotating members; rack gears (640, 642) provided at the front and rear sides of the respective guide and each configured to link to the respective rotating gear (630, 632); a body to support the rotating gears (630, 632) and the rack gears (640, 642), a protrusion (610, 612) being provided at the body; and a linkage to connect the front rack gear and the rear rack gear, the linkage having a guide groove (662, 664) guided by the protrusion (610, 612).