The mower fleet management device is configured to control a plurality of mowers to work in collaboration. Each of the mowers includes an on-board communication module and an on-board positioning and navigation module. The mower fleet management device includes: a map loading module configured to acquire a map of a working land parcel; a control terminal communication module configured to wirelessly communicate with the on-board communication modules to acquire status information of the mowers; and a working region assigning module configured to assign a working region to each of the mowers according to the status information and the map. The on-board positioning and navigation module of each of the mowers guides the mower to work in the corresponding working region according to the assigned working region.