A quarter-foldable rebounder includes a frame of circular configuration, a circular mat, springs and legs. The frame is formed by four one-piece molded quarter-frame arcuate segments having integral pairs of half-fold and quarter-fold hinges and a rod embedded in each of the quarter-frame segments which anchors outer hooked ends of the mat springs extending into recesses and passages in the quarter-frame segments. The rebounder also includes connectors anchoring inner hooked ends of the mat springs to the outer periphery of the mat. Each of the legs is mounted at one end to one of a pair of spaced wells formed in the underside of the quarter-frame segments for undergoing movement between locked and unlocked and erect and folded positions and is received at the other end in the other of the pair of wells when the leg is at the folded position.