An autonomous mobile device is capable of taking action that is suitable to execute a task in accordance with a given situation includes and executes a predetermined task upon autonomously moving to a destination. The autonomous mobile device includes a storage unit that stores an environment map, a laser range finder that acquires peripheral obstacle information, an unknown information identification unit that identifies unknown obstacle information from the peripheral obstacle information, an assessment information acquisition unit that acquires a plurality of types of assessment information including movement information, relative position information, and attribute information that are related to the unknown obstacle, when the unknown obstacle information is identified, and a scenario selection unit that selects, based on the assessment information, one action scenario among a plurality of action scenarios including an action scenario which is defined to execute the task and is other than an action scenario to cancel or continue the execution of the task.