The invention relates to an LISP-based subnet fast moving switching method. The method comprises the following steps: 1, a mobile router MR is connected with a mobile terminal to form a tunnel router xTRA with a mobile subset access serial number A, and registers the tunnel router xTRA; 2, the xTRA sends a mapping registration message to a mapping system, the mapping system sends a mapping push message to the rest tunnel routers (referred to as xTR), and the rest xTRs update the mapping information of the xTRA; 3, the MR and the xTRA maintain an access state; 4, the MR drives the mobile subset to depart the xTRA; 5, the xTRA sends the mapping registration message to the mapping system, the mapping system sends the mapping push message to the rest xTRs, and the xTRs delete the mapping information of the xTRA; 6, the MR drives a tunnel router xTRC with a mobile subset access serial number C and registers the xTRC; 7, the xTRC updates the mapping information of the mapping system; and 8, the MR and the xTRC maintain the access state. By adoption of the LISP-based subnet fast moving switching method provided by the invention, the fast switch of the mobile subnet in a sample area separation network can be realized.