Existence certification and authentication service method and system based on block chain technology

The invention provides an existence certification and authentication service method based on block chain technology. The method comprises the following steps: setting at least a pair of public/private keys for each user in a public block chain, carrying out a hash operation on a digital article to generate a hash value, using the private key to sing the hash value, carrying out the hash operation on the signature to generate a new hash value, and embedding the new hash value in the standard message to generate a new standard message; before broadcasting the new standard message to the public block chain, setting a sender of the new standard message as the address of the user, broadcasting the new standard message, if the new standard message is packaged by the user and the new standard message is confirmed, returning the hash value of the new standard message, and if the block where the new standard message is located is confirmed, returning the hash value of the block; and if the new standard message is not packaged the user, and the legal existence time of the new standard message is overdue, marking the new standard message as ineffective, and reconstructing the new standard message.