A trocar 1 includes a pipe 2 through which a surgical instrument is inserted in a body. The pipe 2 includes a pipe outer cylinder 21 and a pipe inner cylinder 22. The camera 5 is journaled in a distal end notch of the pipe inner cylinder 22 so as to be turnable between a development state in which the camera 5 turns to the outside of the pipe 2 and a storage state in which the camera 5 is stored inside the pipe 2. A coil spring biasing the camera 5 to the development state is accommodated in the pipe inner cylinder 22. The pipe outer cylinder 21 is externally inserted so as to be slidable in an axial direction on the pipe inner cylinder 22, and the pipe outer cylinder 21 stores the camera 5 in the pipe 2 against biasing force of the elastic member while sliding toward a distal end of the pipe 2.
