The invention provides a method for realizing database login authentication based on a Kerberos mechanism, which comprises a preparation authentication stage and a dynamic authentication stage, in the preparation authentication stage, a plug-in is called, a relation between Kerberos and a database is established, and in the dynamic authentication stage, a client sends a user name to a server; the server side analyzes the user name information and determines whether the user name information is a Kerberos authentication mode, and if the user name information is a Kerberos authentication mode, marking is carried out and related authentication data is sent to the client side; the client receives the authentication data and performs client identity authentication; after the verification is passed, the client sends authentication subject information of the server to the KDC, and the KDC performs identity legal information authentication on the client and the server; the client side obtains the authorized bill certificates cred through the bill authorization service and sends the authorized bill certificates cred to the server side; and the server side decrypts the cred to obtain the client side information, the client side information is compared with the client side authentication identifier, if the client side information is the same as the client side authentication identifier, login succeeds, the possibility of login password leakage is completely eradicated through kerberos authentication, and the legality of a data requester and the legality of a data supplier are guaranteed.