Sofa bed with simple structure

The utility model discloses a sofa bed with a simple structure. The sofa comprises two armrests, a first seat cushion, a second seat cushion, a third seat cushion, a first bracket for supporting the first seat cushion, a second bracket for supporting the second seat cushion and a third bracket for supporting the third seat cushion, wherein the sliding rail component is used for being matched withthe second support, the locking component is used for locking the first support and the second support, the second support is movably connected with the third support, and the first cushion and the second cushion are movably connected through a connecting component. The first cushion is pulled to drive the second cushion and the third cushion to act, so that the sofa bed can be changed from a sofastate to a bed body state, and the operation is convenient; and the sofa can be locked by adopting the locking part and the sliding rail part, and the sofa bed is simple in structure, so that the sofa bed is low in cost, not