A foldable bed includes a first frame and a second frame. The first frame has a first board put thereon. A first connector is connected to the front end of the first frame and has a first pin hole and a first aperture which is located below the first pin hole. The second frame has a second board put thereon. A second connector is connected to the rear end of the second frame and has a second pin hole and a second aperture which is located below the first pin hole. A pivot extends through the first and second apertures to pivotably connect the first frame to the second frame. When the first and second frames are extended. A pin extends through the first and second pin holes.