1. An operating area determination method, comprising: generating a plurality of depth maps of a target scene at a plurality of time points; comparing a difference between at least two specific depth maps among the depth maps to identify a moving object in the target scene and defining a position of the moving object in the target scene as a reference point; obtaining a standard point in the target scene according to the reference point and a specific depth corresponding to the reference point; and determining an effective operating area for controlling an electronic apparatus in the target scene according to the reference point and the standard point.