The invention discloses a certificate request message sending method and apparatus, and a certificate request message receiving method and apparatus. The method comprises the following steps: obtaining, by a virtual network function VNF entity, a disposable credential and a first credential request message; parsing the disposable credential to obtain a first security key and a first hmac key; processing the first certificate request message by using the first security key and the first hmac key to generate a second certificate request message, wherein the second certificate request message comprises an identity identifier used for identifying the VNF entity; sending the second certificate request message to an authentication center, so that the authentication center authenticates the identity of the VNF entity. In the method, encryption processing is performed on the certificate request message by using the security key and the hmac key, thereby not only realizing the identity verification of the VNF entity that sends the request, but also protecting the security and integrity of the transmission of the request message.