A work machine management device includes a manned-vehicle-data acquisition unit configured to acquire position data of a manned vehicle including a first direction indicator and operation data of the first direction indicator, a target-travel-route generation unit configured to generate a target travel route for a work machine, a blinker-data setting unit configured to set blinker data for controlling a second direction indicator of the work machine on the basis of link data obtained by associating the position data of the manned vehicle and the operation data of the first direction indicator, and an output unit configured to output the blinker data to the work machine traveling along the target travel route.