Aiming at the narrow-band characteristic of the short wave network, an identity authentication scheme is designed based on USB Key and PIN code. The scheme adopts the challenge/response mechanism, takes the thought of five authentication factors in 3G authentication scheme for reference, and improves the generation mechanism of five authentication factors by using HMAC algorithm. The scheme reduces the data cost in the process of the authentication, meets the bandwidth requirements of the short wave network, and has high security.