The invention discloses an oral endoscope detection system and a detection method thereof. The oral endoscope detection system comprises an insertion portion, a camera unit arranged in the insertion portion, a displacement information acquisition module, an operation mode setting module, a signal transmission module, an operation unit connected with the insertion portion, an image control processing module and a display device. An image displayed on the display device is a positive visual image of a subject part by using the invention, so that the operator can better operate a subject oral cavity to avoid the situation that the operator cannot make correct judgment because detection images taken by oral endoscopes in the prior art are upside down or skew.
