The present invention discloses a network security HTTP negotiation method and related devices. the method comprises: a server receiving an HTTP request message with a header field sent by a terminal, wherein the header field indicates security mechanism(s) supported by the terminal, or the security mechanism(s) supported by the terminal and indication parameter(s) which show that the terminal has been in an accessing safety state; the server parsing the HTTP request message, and sending a response message with negotiated security mechanism(s) supported by the server and priority parameter(s) thereof to the terminal according to the result of the parsing if the header field of the request message indicates the security mechanism(s) supported by the terminal; and the server receiving another HTTP request message sent by the terminal again to authenticate security mechanism(s) selected by the terminal, wherein the header field of the request message indicates the security mechanism(s) selected by the terminal according to the response message and the priority parameter(s) of the security mechanism(s). The invention expands the HTTP protocol, solves the problem that the terminal security mechanisms are difficult to be deployed, and improves the network service quality.