An option code providing circuit includes a plurality of resistive random access memory cells and a controller. The controller determines whether to provide a control signal to operate a heavy forming operation on the resistive random access memory cells or not. Wherein, the controller performs a read operation on the resistive random access memory cells to determine a bit number of the resistive random memory cell which is heavy formed, and the option code is determined by the bit number of resistive random access memory cell which is heavy formed or a bit number of the resistive random access memory cell which is not heavy formed.