A scope unit 2 including a control unit 3 and an insertion portion 4 is attached to a main unit 1 via a scope connector 5. An optical adaptor 8 is attached to a tip of the insertion portion 4. The CCD 31, HICs 32, 33, and the thermistor 34 are attached to the tip of the insertion portion 4. A liquid crystal module 36 is attached to the optical adaptor 8. A barrier circuit 64 limits energy supplied to these components in a circuit disposed in the scope unit 2. By disposing the barrier circuit 64 in the scope connector 5, the portion extending from the barrier circuit 64 to, i.e., the control unit 3, the insertion portion 4, and the optical adaptor 8 are of the explosion-proof construction. Thus, these can be used in a hazardous explosive location. Thus, an endoscope apparatus that can be used in combustible gas or dust can be provided.