A rotating field sensor for detecting an angle ψ that a direction of a rotating magnetic field in a reference position forms with respect to a reference direction, in which the rotating field sensor comprises: a first detection circuit that detects an intensity of a component of the rotating magnetic field in a first direction and outputs a first signal indicating the intensity; a second detection circuit that detects an intensity of a component of the rotating magnetic field in a second direction and outputs a second signal indicating the intensity; and an arithmetic circuit that calculates, based on the first and second signals, a detected angle ψ value (θ) having a correspondence relationship with the angle ψ that the direction of the rotating magnetic field in the reference position forms with respect to the reference direction; each of the first and second detection circuits includes at least one row (R11; R21) of magnetoresistive elements; each of the at least one row (R11; R21) of magnetoresistive elements is composed of a plurality of magnetoresistive elements (R111; R112; R211; R212) connected in series; each of the plurality of magnetoresistive elements (R111; R112; R211; R212) has a magnetization pinned layer whose magnetization direction (D111; D112; D211; D212) is pinned, a free layer whose magnetization direction varies according to the direction of the rotating magnetic field, and a nonmagnetic layer disposed between the magnetization pinned layer and the free layer; the number of the plurality of magnetoresistive elements (R111; R112; R211; R212) forming each row (R11; R21) of magnetoresistive elements is an even number equal to or greater than two; the plurality of magnetoresistive elements (R111; R112; R211; R212) forming each row (R11; R21) of magnetoresistive elements include one or more pairs (R111 and R112; R211 and R212) of magnetoresistive elements; in each pair (R111 and R112; R211 and R212) of magnetoresistive elements, the magnetization directions (D111; D112; D211; D212) of the magnetization pinned layers in the two magnetoresistive elements making up the pair form a predetermined relative angle ψ other than 0° and 180°; the at least one row of magnetoresistive elements in the first detection circuit does not include any magnetoresistive element that has a magnetization pinned layer whose magnetization direction is pinned in the first direction or in a direction opposite to the first direction; and the at least one row of magnetoresistive elements in the second detection circuit does not include any magnetoresistive element that has a magnetization pinned layer whose magnetization direction is pinned in the second direction or in a direction opposite to the second direction. a first detection circuit that detects an intensity of a component of the rotating magnetic field in a first direction and outputs a first signal indicating the intensity; a second detection circuit that detects an intensity of a component of the rotating magnetic field in a second direction and outputs a second signal indicating the intensity; and an arithmetic circuit that calculates, based on the first and second signals, a detected angle ψ value (θ) having a correspondence relationship with the angle ψ that the direction of the rotating magnetic field in the reference position forms with respect to the reference direction;