A torque detection device, comprising: a torsion bar that couples a first shaft member and a second shaft member to each other; a permanent magnet that is fixed to the first shaft member, and that forms a magnetic field around the first shaft member; a magnetic yoke (81, 82) that is fixed to the second shaft member, that is arranged within the magnetic field formed by the permanent magnet, and that forms a magnetic circuit of which a magnetic flux density changes in response to a change in a position of the magnetic yoke (81, 82) relative to the permanent magnet due to torsion of the torsion bar; a magnetic flux collecting ring (41, 42) that collects magnetic fluxes from the magnetic yoke (81, 82); and a magnetic sensor that detects magnetic fluxes, which are generated in the magnetic circuit, via the magnetic flux collecting ring (41, 42), characterized in comprising an annular magnetic flux collecting unit that includes: an annular holder formed by resin molding and having a through-hole (53A; 58A) that passes through the holder in a radial direction; the magnetic flux collecting ring (41, 42) which is fitted to an inner periphery of the holder so as not to cover the through-hole (53A; 58A); and a magnetic shield that is fitted to an outer periphery of the holder so as to cover the through-hole (53A; 58A) and that reduces influence of an external magnetic field on the magnetic circuit, the magnetic flux collecting unit being arranged so as to surround the magnetic yoke (81, 82); and a sensor housing that is made of resin supplied onto an outer periphery of the magnetic flux collecting unit, and that is formed so as to be integrated with the magnetic flux collecting unit. a torsion bar that couples a first shaft member and a second shaft member to each other; a permanent magnet that is fixed to the first shaft member, and that forms a magnetic field around the first shaft member; a magnetic yoke (81, 82) that is fixed to the second shaft member, that is arranged within the magnetic field formed by the permanent magnet, and that forms a magnetic circuit of which a magnetic flux density changes in response to a change in a position of the magnetic yoke (81, 82) relative to the permanent magnet due to torsion of the torsion bar; a magnetic flux collecting ring (41, 42) that collects magnetic fluxes from the magnetic yoke (81, 82); and a magnetic sensor that detects magnetic fluxes, which are generated in the magnetic circuit, via the magnetic flux collecting ring (41, 42), characterized in comprising an annular magnetic flux collecting unit that includes: an annular holder formed by resin molding and having a through-hole (53A; 58A) that passes through the holder in a radial direction; the magnetic flux collecting ring (41, 42) which is fitted to an inner periphery of the holder so as not to cover the through-hole (53A; 58A); and a magnetic shield that is fitted to an outer periphery of the holder so as to cover the through-hole (53A; 58A) and that reduces influence of an external magnetic field on the magnetic circuit, the magnetic flux collecting unit being arranged so as to surround the magnetic yoke (81, 82); and a sensor housing that is made of resin supplied onto an outer periphery of the magnetic flux collecting unit, and that is formed so as to be integrated with the magnetic flux collecting unit.