An operation support system performing treatment on a target tissue while observing using an image capturing unit, using a treatment unit installed at a distal end side of a manipulator, a distal end seen from a fixing end of the manipulator, includes: the manipulator having joints corresponding to degrees of freedom and including at least two redundant joints having a redundant relationship among the joints an operating unit configured to provide operating information corresponding to the degrees of freedom a positional relationship calculation unit calculating a switching positional relationship between the target tissue or the treatment unit and the image capturing unit and a control unit controlling an operation of the joint according to the operating information. The control unit controls the manipulator using one redundant joint as a driving joint and the other redundant joints as a fixing joint based on the switching positional relationship.
