Disclosed herein is a 4-way lumbar support capable of automatically adjusting a vertical curved position and an amount of curvature of a lumbar plate, while securely supporting the lumbar plate even when a large load, such as the rear-end collision of a vehicle, is applied to the lumbar plate. In addition, the 4-way lumbar support can adjust an amount of forward curvature of the lumbar plate using a pusher including a pair of hinge members, thereby enabling the amount of forward curvature of the lumbar plate to be adjusted across a wider range without increasing the thickness of a seat back in the forward and backward directions thereof.