In an endoscopic system, when an affected area of a biomedical tissue in an image is treated with a scalpel and a holding pair of forceps which movably extend from a distal portion of an endoscope through the endoscope while the image taken by the endoscope in a body cavity in a time-series manner is being observed, a treatment is performed in which the holding pair of forceps holds the affected area detached from the biomedical tissue by the scalpel. When any motion is detected in the distal portion of the endoscope included in the image, a motion direction and a motion amount of the distal portion of the endoscope attributed to the motion are detected, and the distal portion of the endoscope is curved to return the scalpel to an original treatment position.
