Provided is a manipulator (1) equipped with a movable part (3), a drive part (4) that generates power to be supplied to the movable part (3), an elongated, flexible long guide member (2) in which the movable part (3) is attached to one end and the drive part (4) is attached to the other end, an elongated tension transmitting member (5) that transmits the power of the drive part (4) to the movable part (3) by means of tension, and a tension adjusting mechanism (6) that adjusts the tension of the tension transmitting member (5), wherein: the long guide member (2) is equipped with an elongated, flexible guide tube (11) having a lumen (10) through which the tension transmitting member (5) passes in the longitudinal direction, and an outer case (12) that covers the outer periphery of the guide tube (11), has a proximal end part (13) that is movably provided to the drive part (4) in the longitudinal direction of the guide tube (11), and is more rigid than the guide tube (11); and the tension adjusting mechanism (6) adjusts the position of the proximal end part (13) of the outer case (12) with respect to the drive part (4) along the longitudinal direction of the guide tube (11).L'invention fournit un manipulateur (1) qui est équipé : d'une partie mobile (3) ; d'une partie entraînement (4) qui génère une force motrice alimentant la partie mobile (3) ; d'un élément de guidage allongé (2) souple et fin sur lequel est installée la partie mobile (3) à une extrémité et la partie entraînement (4) à l'autre extrémité ; d'un élément de transmission à force de traction (5) fin qui transmet la force motrice de la partie entraînement (4) à la partie mobile (3) au moyen d'une force de traction ; et d'un mécanisme d'ajustement de force de traction (6) ajustant la force de traction de l'élément de transmission à force de traction (5). L'élément de guidage allongé (2) est équipé : d'un tube de guidage (11) souple et fin possédant une lumière (10) traversée par l'élément de transmission à