An active drive type medical apparatus includes: an active mechanism having a rotatable joint provided near the distal end of a long member; an active mechanism driving section; a position/attitude detecting section configured to detect a position/attitude of the active mechanism; an instruction input section for performing instruction input of the position/attitude of the active mechanism; and a force calculating section configured to calculate, on the basis of the instruction input of the position/attitude, a force corresponding to a net external force acting on the active mechanism, by subtracting an estimated driving force estimated in the case where the active mechanism in a no-load state is driven, from a driving force required in the case where the active mechanism is actually driven by the active mechanism driving section from the position/attitude before the instruction input to the instructed and inputted position/attitude.