A dental treatment observation system includes a photographing unit supported with a first auxiliary arm at a front end of a support arm extending from a stand and a stereoscopic display unit supported with a second auxiliary arm at the front end of the support arm. The stand allows the photographing unit and stereoscopic display unit together to be widely moved and the first and second auxiliary arms allow the units to be separately moved in optional directions. The system is appropriate for dental treatment and is capable of reducing fatigue of a dentist during treatment.