Electronic contract system and contract signing method based on block chain evidence storage

The invention provides an electronic contract system and contract signing method based on block chain evidence storage. The method comprises the following steps: a sender uploads a contract or selects a contract template through an electronic contract system, carries out digital signature on the contract by using a digital certificate issued by an authoritative CA (Certificate Authority), and adds a national authorization timestamp service into the contract; the electronic contract is sent to a signing end, the electronic contract returned by the contract signing end is received, and the electronic contract comprises a signing time timestamp and an electronic seal of an electronic contract signing party; and setting signing parties and a sequence according to the electronic contract sender, and receiving the electronic contracts returned by all the signing parties and the final electronic signature to complete signing. The electronic contract platform records all node information in the contract signing proce