The invention discloses a document
encryption and decryption method, device and
system. The document
encryption and decryption method comprises the steps of receiving an
electronic document downloading request sent by a
client side; generating an
encryption secret key, encrypting file content corresponding to a
document identifier by utilization of the encryption secret key, and generating an encrypted document; reading a stored user public key according to
user information, and encrypting the encryption secret key to generate secret key information by utilization of the user public key; correspondingly storing the
document identifier and the secret key information; and sending the encrypted document to the
client side. An
electronic document after being downloaded by a user is the encrypted document, the encryption secret key is obtained through the fact that a user private key in certificated equipment needs to be used for decrypting the secret key information stored in a
server, and then the encryption secret key is used for decrypting the encrypted document to obtain the
electronic document. Even the encrypted document after being downloaded is divulged, due to the fact that the certificated equipment is unavailable to be connected to the
server to conduct decryption on the downloaded encrypted document, the content of the electronic document can not be read, and due to the fact that the electronic document is stored in an
internal memory and can not be copied directly, safety performance is high.