An image managing method includes dividing the original moving image into a header and a body and generating the group hash value of the header portion, generating the hash value of each item of still image data, connecting the group hash value of the header portion and the hash value of each item of still image data to generate connected hash values, generating a group of the connected hash values as a hash value list, generating the hash value of a Huffman table on the basis of cutting out one still image, and signing to generate signature information of the original moving image, using the group hash value of the header portion, the hash value of the Huffman table, and the hash list as verification data of the original moving image, by adding a digital signature of a video recording terminal to it.