Abstract: This application relates to a device type identification method performed by a computer device. The method includes: transmitting a port open/closed state probe packet to at least two target devices; receiving port open/closed state information returned by the at least two target devices in response to the port open/closed state probe packet, wherein the port open/closed state information comprises port open/closed state vectors indicating whether each port of the at least two target devices is open or closed; extracting a port open/closed state feature from the port open/closed state information; performing decision classification on the port open/closed state feature through a decision tree classifier; and determining a device type of each of the at least two target devices according to a result obtained from the decision classification.