PURPOSE: A bed frame of which width is freely adjustable and which is easily assembled is provided. CONSTITUTION: A bed frame comprises: a bottom support(20) on which mattress is placed; a support(30) which is placed at both sides of the bottom support and coupled by a connection part; the mattress which is placed on the inside of the outer frame; and a bottom plate(60) on which the mattress is laid. The bottom support is divided in a constant interval and has outer frame.
