Abstract: The object of the invention is a sofa bed (1) which can be used in sofa position and in bed position, and which sofa bed (1) comprises a frame (2) which comprises end sections (3,5), a seating section (9) connected to the frame (2), and a back section (7), which is pivotally connected to the frame (2) in at least two turning points and which comprises a back side (45) of the sofa at the end sections (3,5) of which is a turning guide (25) and preferably upwards orienting directing guide (27) and which turning guide (25) and directing guide (27) are generally elongated in form and substantially at an angle with each other a first turning point is arranged to travel back and forth the turning guide (25) and a second turning point in cross direction in a distance from the first turning point, is arranged to travel back and forth the directing guide (27) in order to change the position of the back section (7) between the sofa position and bed position and to turn the back side (45) of the back section (7) upwards.