A foldable base is applied to a display to be folded up for easy storage. The foldable base includes a first portion and a second portion, wherein the first portion is pivotably connected to the second portion via a shaft. The main body of the shaft, positioned at a turning space within the foldable base, at least includes a positioning plane and a curved surface. When the first portion is pivoted around the second portion, the main body of the shaft is simultaneously rotated in the turning space. Since the main body of the shaft is physically interfered by the turning space, the first portion of the foldable base can be spontaneously sent back to a first position (such as a start-to-rotate position) or folded up to a second position (such as a storage position) after the first portion is rotated to a certain angle.