A remote operation device for remotely operating a working machine including a working mechanism, the remote operation device comprising: remote wireless communication equipment having a communication function with real machine wireless communication equipment mounted on the working machine; a remote image output device; a remote operation mechanism; a remote control element that recognizes an operation form of the remote operation mechanism by an operator and causes the remote wireless communication equipment to transmit a command signal corresponding to the operation form to the real machine wireless communication equipment; a first output control element that causes the remote image output device to output a work environment image including a working unit of the working mechanism acquired through an imaging device mounted on the working machine, transmitted from the real machine wireless communication equipment, and received by the remote wireless communication equipment; and characterized in that the remote operation device further comprises a second output control element that estimates, based on an operation form of the remote operation mechanism at a first point in time recognized by the remote control element, a space occupying form of the working unit at a second point in time later than the first point in time, superimposes, on the work environment image, at a third point in time included in a period from the first point in time to the second point in time, an indicator image representing the estimated space occupying form of the working unit at the second point in time without spoiling visibility of the working unit, and causes the remote image output device to output the indicator image. remote wireless communication equipment having a communication function with real machine wireless communication equipment mounted on the working machine; a remote image output device; a remote operation mechanism; a remote control element that recognizes an operation form of the remote operation mechanism by an operator and causes the remote wireless communication equipment to transmit a command signal corresponding to the operation form to the real machine wireless communication equipment; a first output control element that causes the remote image output device to output a work environment image including a working unit of the working mechanism acquired through an imaging device mounted on the working machine, transmitted from the real machine wireless communication equipment, and received by the remote wireless communication equipment; and characterized in that the remote operation device further comprises a second output control element that estimates, based on an operation form of the remote operation mechanism at a first point in time recognized by the remote control element, a space occupying form of the working unit at a second point in time later than the first point in time, superimposes, on the work environment image, at a third point in time included in a period from the first point in time to the second point in time, an indicator image representing the estimated space occupying form of the working unit at the second point in time without spoiling visibility of the working unit, and causes the remote image output device to output the indicator image.