Document sharing method and device

The embodiment of the invention relates to a document sharing method and device, a cloud server side, a terminal and a document sharing system.The document sharing method is applied to the cloud server side and comprises the steps that a target document is obtained and stored; the target document is shared to a target group, and the target group comprises more than two group members; according to the document fingerprint of the target document, generating and storing mark information of the target document; the mark information comprises document attribute information and target group association information; the document attribute information is used for indicating that the target document is an initial document or a variant document; the target group association information is used for establishing association between the target document and the target group; and according to the target group associated information of the target document, sending the target document to a terminal used by each group member i