A document management system includes a management apparatus and plural processing apparatuses. Each of the plural processing apparatuses includes an acquisition unit and a transmitter. The acquisition unit acquires a document and information on a destination to which the document is transmitted. The transmitter transmits metadata of the document to the management apparatus and transmits a protected document generated from the document to the destination. The metadata includes the information on the destination. The management apparatus includes a memory and a response unit. The memory stores metadata of documents received from the plural processing apparatuses. The response unit responds to a request for metadata corresponding to a document by returning metadata of the document which is stored in the memory.