PURPOSE: To allow the circuit to cope with revision of a generation polynomial on its occurrence without need of large scale revision of the circuit.

CONSTITUTION: The circuit is provided with an n-stage holding circuit 1 holding the arithmetic result when a highest degree of a generation polynomial used for a redundancy code check (CRC) arithmetic is up to n-th degree, a recursive code selection circuit 2 selecting and outputting a recursive code among outputs of the n-stage holding circuit 1 according to the input of coefficients for the generation polynomial, an exclusive OR circuit 13 taking exclusive OR between a binary information input being an arithmetic object and the recursive code and outputting the OR output to a 1st stage holding circuit, OR circuit 4-5 ORing the output of the exclusive OR circuit 13 and each coefficient input of the generation polynomial whose output is fed to the exclusive OR circuit of the n-stage holding circuit 1.