An adjustable bed frame includes a frame having a first retractable device in a horizontal direction for securing a first supporting unit. The first supporting unit includes a second retractable device for securing a first mattress. Second supporting units are provided at respective sides of the frame. Each second supporting unit has a third retractable device therein for securing a second mattress. The first mattress is connected with a soft pad. The second mattress is connected with a soft pad. The first supporting unit can be pulled outward in a horizontal direction. Both the first mattress and the second mattress can be lifted upward, and the soft pads can be turned for different purposes.