PROBLEM TO BE SOLVED: To provide an endoscope system whose main body can be minimized even in a case where a battery quickly rechargeable in an atmosphere including flammable gas or dust is used.SOLUTION: An endoscope system 1 is provided with a main body 3 into which an insertion part 2 is connected, and a battery 4 to be connected with the main body 3 and to supply electric power to an electric circuit in the main body 3. The main body 3 has positive electrode terminals E1 to E3 and negative electrode terminals E5 to E7, for connecting with the battery 4. The battery 4 has plural positive electrode terminals A1 to A4 and negative electrode terminals A5 to A8, whose number are greater than those of the main body 3. When the battery 4 is connected with the main body 3, the positive electrode terminals E1 to E3 provided on the main body 3 are connected to the positive electrode terminals A1 to A3 of the battery 4, respectively.