A detection device for detecting respective end positions in left and right steering directions of a mechanism portion of a turning device, the device comprising: a steering angle detection unit configured to detect a steering angle (θ h) in the mechanism portion; an actuator driving the mechanism portion; a torque detection unit configured to detect steering torque (T dct) to the mechanism portion; and a limit position detection unit configured to detect respective limit positions in the left and right steering directions in the mechanism portion, wherein the limit position detection unit starts detecting the limit position of the steering angle (θ h) in a direction of a torque value when the torque value of the mechanism portion loaded by at least one of a drive force from the actuator and the steering torque (T dct) detected by the torque detection unit exceeds a first threshold (Th l), characterized in that the limit position detection unit: continues to detect the limit position by storing a peak value of the steering angle (θ h) detected by the steering angle detection unit as the limit position while the torque value of the mechanism portion is between the first threshold (Th l) and a second threshold (Th u) greater than the first threshold (Th l), and ends the detection of the limit position by regarding the stored limit position as the end position in the steering direction indicated by the torque value when the torque value of the mechanism portion exceeds the second threshold (Th u). a steering angle detection unit configured to detect a steering angle (θ h) in the mechanism portion; an actuator driving the mechanism portion; a torque detection unit configured to detect steering torque (T dct) to the mechanism portion; and a limit position detection unit configured to detect respective limit positions in the left and right steering directions in the mechanism portion, wherein the limit position detection unit starts detecting the limit position of the steering angle (θ h) in a direction of a torque value when the torque value of the mechanism portion loaded by at least one of a drive force from the actuator and the steering torque (T dct) detected by the torque detection unit exceeds a first threshold (Th l), characterized in that the limit position detection unit: continues to detect the limit position by storing a peak value of the steering angle (θ h) detected by the steering angle detection unit as the limit position while the torque value of the mechanism portion is between the first threshold (Th l) and a second threshold (Th u) greater than the first threshold (Th l), and ends the detection of the limit position by regarding the stored limit position as the end position in the steering direction indicated by the torque value when the torque value of the mechanism portion exceeds the second threshold (Th u). continues to detect the limit position by storing a peak value of the steering angle (θ h) detected by the steering angle detection unit as the limit position while the torque value of the mechanism portion is between the first threshold (Th l) and a second threshold (Th u) greater than the first threshold (Th l), and ends the detection of the limit position by regarding the stored limit position as the end position in the steering direction indicated by the torque value when the torque value of the mechanism portion exceeds the second threshold (Th u).