Provided is a system which can avoid instability of an operating state of a working machine, when switching a remote operation actor of the working machine. In a case where a state of one or both of a working machine 40 or a first operator is a specified state when the working machine 40 is remotely operated through a first remote operation apparatus 10, a first notification corresponding to the specified state is transmitted to a remote operation server 30. In the remote operation server 30, a second remote operation apparatus 20 which is appropriate in view of content of the first notification is selected as the remote operation actor of the working machine 40.