The invention provides a session keeping method and device used for load balancing equipment. The method comprises the following steps: acquiring a common characteristic of a first message of a clientand a second message of a server; recording position information of the common characteristic in the first message; and when a third message is received, if the third message is judged to be matchedwith the common characteristic according to the position information, then representing that the third message and the first message belong to a same session, and sending the third message to the server, so as to realize session keeping. According to the scheme of the invention, messages belonging to the same session can be identified through simple message characteristic comparison, the session is not needed to be saved, the operating speed of a system is not affected, and cookie is not needed, thus potential safety hazards are avoided. At the same time, automatic and active comparison and characteristic extraction of the messages are achieved, and there is no need to indicate where the characteristics are by manual configuration in advance, so that a page configuration operation is reduced, a user can still realize session keeping under load balancing even if the user cannot check the messages, and the user experience is improved.