An encryption processing device comprising: an encryption processing part configured to divide configuration bits of data to be data processed into a plurality of lines, and to input, and to repeatedly execute data conversion processing applying a round function to each line of data as a round calculation; and a key scheduling part configured to output round keys to a round calculation executing unit in the encryption processing part; wherein the key scheduling part is a replacement type key scheduling part configured to generate a plurality of round keys, by dividing a secret key stored beforehand into a plurality of parts without using a non-linear function; and wherein the plurality of round keys generated from respective ones of said plurality of divided parts, or plurality of round keys each generated from a respective concatenation of two of the plurality of divided parts, are output to a round calculation executing unit sequentially executing in the encryption processing part such that a constant sequence is not repeated, wherein the output plurality of generated round keys form a group; wherein the key scheduling part is configured to output a plurality of groups by supplying the output plurality of generated round keys in a different sequence in each group, or outputting a plurality of round keys each generated from a different respective concatenation of two of the plurality of divided parts when keys are generated by concatenation of divided parts; and wherein the key scheduling part is configured to perform control processing of the key supply sequence corresponding to the round calculation executing unit at units of the set groups of generated round keys. an encryption processing part configured to divide configuration bits of data to be data processed into a plurality of lines, and to input, and to repeatedly execute data conversion processing applying a round function to each line of data as a round calculation; and a key scheduling part configured to output round keys to a round calculation executing unit in the encryption processing part; wherein the key scheduling part is a replacement type key scheduling part configured to generate a plurality of round keys, by dividing a secret key stored beforehand into a plurality of parts without using a non-linear function; and wherein the plurality of round keys generated from respective ones of said plurality of divided parts, or plurality of round keys each generated from a respective concatenation of two of the plurality of divided parts, are output to a round calculation executing unit sequentially executing in the encryption processing part such that a constant sequence is not repeated, wherein the output plurality of generated round keys form a group; wherein the key scheduling part is configured to output a plurality of groups by supplying the output plurality of generated round keys in a different sequence in each group, or outputting a plurality of round keys each generated from a different respective concatenation of two of the plurality of divided parts when keys are generated by concatenation of divided parts; and wherein the key scheduling part is configured to perform control processing of the key supply sequence corresponding to the round calculation executing unit at units of the set groups of generated round keys.