The invention provides private a method for realizing synchronous office between a private application and communication software by using documents. The method includes the following steps that: business data are documentated; a connection between the private application and a communication server is created, and the connection is maintained; a staff structural tree or group is organized; communication staff or a group in the staff structural tree is selected; a document is shared among the staff or the group; and the staff or users in the group operate the shared document and handle business, the communication software automatically intercepts chat records and a handling flow document; and a document generated after business handling, the handling flow document and a chat record document are sent to the private application. According to the method for realizing the synchronous office between the private application and the communication software by using the documents provided by the invention, the business data are documentated and can be printed on paper, so that the users can realize paper-based office work more intuitively and more efficiently, and the business handling document can be shared in the mobile communication group, and the shared document can be operated through the communication software, so that business handling can be achieved, and at the same time, document automatic trace-keeping handling can be realized.