The present application provides a dynamic graphical password-based network registration method and system. The method includes: a server receives a registration request transmitted by a client, selects positioning factors from a positioning factor library based on a structure of a full-element dynamic factor table, generates positioning factor strings, and transmits the generated positioning factor strings to the client; the client generates full-element dynamic factor tables based on the structure of the full-element dynamic factor table and the positioning factor strings, wherein a user inputs two dynamic graphical passwords through the full-element dynamic factor tables, and transmits registration information including a user name and the positioning rules corresponding to the dynamic graphical passwords to the server; wherein if the registration information is correct, the positioning rule in the registration information is used as the password of the user. In the method, the input dynamic graphical password is used as the password stored for the user, which is securer, easy to remember, and hard to crack as compared with a conventional password consisting of fixed numerals or characters.