The present invention provides a recording method and recording system of log, the method comprising the steps of: generating an IP log, the content recorded by the IP log comprising at least an IP address and the operation being performed; finding the IP address in the IP log; replacing the found IP address with a user's information to obtain the ID log. With the present invention, the IP log is converted into ID log, in this way, the true user of the computer may be directly obtained through the ID log, the log information may provide the administrator of the system with very useful information on what is hazardous to the safety, which is significantly advantageous to the secret and security of the network of a company or an enterprise.