Many new risks of electric power operation have emerged along with the development of the Ethernet used in substation communication systems. With the substation switching operation as the research object and the control model of IEC 61850 as the groundwork， it is considered that the substation operation should be an access process based on the Ethernet and the anti-maloperation measure will mainly be manifested as the regulations for access behaviors， including the judgment by the control object if the client has appropriate access authority. In addition， a method of telecontrol anti-maloperation is proposed which can successfully perform the misoperation preventing function and the idle stroke preventing function similar to those of the current microcomputer mal-operation preventing system.