The present disclosure provides a mobile device and a method of changing the centroid thereof. The mobile device includes a device body, having a processor disposed therein; and a centroid changing device, including a guide rail disposed on the device body, a weight assembly slidably disposed on the guide rail, and a driving device coupled to the weight assembly, wherein the processor is electrically coupled to the driving device, and controls the weight assembly to slide along the guide rail via the driving device, to change the centroid of the device body.