The invention relates to a circuit board, an image forming apparatus having the circuit board, and a method of managing reuse information of the circuit board. The circuit board includes a main part on which a processor is mounted, a cut part to be cut off from the main part at a cut section before the board is reused, and a conductor pattern wired through the cut part via the cut section and to be cut off into a plurality of patterns at the cut section as the cut part is cut off. When the electric power is supplied, the processor detects a difference in signal level between a level of a signal output from the conductor pattern before the cut part is cut off, and a level of the signal output from the conductor pattern after the cut part is cut off, to output a detection result and to determine a number of times the board is reused.