Method and system for establishing data path

Disclosed is a method for establishing a data path. The method comprises: when receiving a data packet sent by an opposite end to a terminal, an opposite access gateway sending a position information query request to a home server; or when receiving a data packet sent by an opposite end to a terminal, an opposite access gateway sending the data packet to a home server; when receiving the position information query request or the data packet, the home server matching connection information of the opposite end with connection information registered by the terminal, and if the two pieces of information do not match, notifying the terminal of establishing a bearer based on the connection information of the opposite end; and the terminal establishing a bearer according to the connection information of the opposite end and a new terminal access gateway, and registering new position information and connection information on the home server. Also disclosed are a system for establishing a data path and a home server.