The invention discloses an authentication method of a credible device under the network environment, which comprises the following steps: firstly, installing and operating a monitoring program to all computers in a network; secondly, uniformly registering and authorizing the credible device in an Authorized Center before using, so that the credible device is provided with exclusive identity information; and thirdly, reading and verifying the identity information of a device to be authenticated by using a computer to be accessed after the device to be authenticated is connected with any computers in the network; determining the device to be authenticated to be the credible device and permitting the credible device to be accessed if the vetification is realized, or else, directly determining the device to be authenticated to be an illegal device and refusing the illegal device to be accessed. The method can effectively prevent external computers and other devices from being accessed into a unit in-house network through various legal or illegal means, thereby not only effectively controlling the management of unit movable storage devices, the computers and other devices, preventing divulgence cases from occurring, and protecting the safety of the system, but also improving the efficiency of unit information.