A master-slave manipulator comprising: a master input device configured to operate a slave manipulator which comprises joints corresponding to a plurality of degrees of freedom, the master input device comprising: an operating unit capable of being changed in position and orientation by an operator's operation and configured to provide command values of a position and orientation of the slave manipulator as the position and orientation thereof change; and detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) of two or more systems configured to individually detect different physical quantities related to the operating unit in order to detect the position and orientation of the operating unit; a first control unit configured to calculate a plurality of positions and orientations of the operating unit based on the physical quantities individually detected by the detection units of two or more systems; and a second control unit configured to calculate the command values of the position and orientation of the slave manipulator based on the positions and orientations of the operating unit calculated by the first control unit and drivingly control the slave manipulator based on the calculated command values of the position and orientation of the slave manipulator, characterized in that the first control unit is configured to determine whether or not differences between the positions and orientations of the operating unit calculated, based on the physical quantities individually detected by the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) of two or more systems are within a predetermined range, to calculate the command values of the position and orientation of the slave manipulator if the differences are within the predetermined range, to perform error processing if the differences are not within the predetermined range, to inspect after the error processing whether or not the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) are faulty, and when it has been inspected that the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) are faulty, to drivingly control the slave manipulator using a faultless signal. a master input device configured to operate a slave manipulator which comprises joints corresponding to a plurality of degrees of freedom, the master input device comprising: an operating unit capable of being changed in position and orientation by an operator's operation and configured to provide command values of a position and orientation of the slave manipulator as the position and orientation thereof change; and detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) of two or more systems configured to individually detect different physical quantities related to the operating unit in order to detect the position and orientation of the operating unit; an operating unit capable of being changed in position and orientation by an operator's operation and configured to provide command values of a position and orientation of the slave manipulator as the position and orientation thereof change; and detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) of two or more systems configured to individually detect different physical quantities related to the operating unit in order to detect the position and orientation of the operating unit; a first control unit configured to calculate a plurality of positions and orientations of the operating unit based on the physical quantities individually detected by the detection units of two or more systems; and a second control unit configured to calculate the command values of the position and orientation of the slave manipulator based on the positions and orientations of the operating unit calculated by the first control unit and drivingly control the slave manipulator based on the calculated command values of the position and orientation of the slave manipulator, characterized in that the first control unit is configured to determine whether or not differences between the positions and orientations of the operating unit calculated, based on the physical quantities individually detected by the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) of two or more systems are within a predetermined range, to calculate the command values of the position and orientation of the slave manipulator if the differences are within the predetermined range, to perform error processing if the differences are not within the predetermined range, to inspect after the error processing whether or not the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) are faulty, and when it has been inspected that the detection units (13, 200, 202, 204, 206, 208, 210, 600, 650, 700) are faulty, to drivingly control the slave manipulator using a faultless signal.