Embodiments of the present invention provide a packet receiving method, a deep packet inspection device and system, which relates to the field of communications. The packet receiving method includes: receiving a service request packet sent by a terminal device, where the packet carries a terminal domain name indicating the terminal device and a server domain name indicating a service server required by the service request; resolving the received server domain name to obtain a service server Internet protocol (IP) address; and discarding the packet if the resolved service server IP address does not belong to the preset service server IP address corresponding to the received terminal domain name in a preset list. Embodiments of the present invention are applied to the processing of the packet.