To provide a position measuring apparatus by which the position of a moving body can be found on the basis of the orientation of the moving body and on the basis of the movement distance of a steering wheel without using a steering angle as far as possible.

The position measuring apparatus is provided with a judgment part 10-1 which judges whether the moving body is swiveled and moved and a position calculation and processing part 10-2. When the judgment part 10-1 judges that the moving body is not swiveled and moved the processing part 10-2 measures the position of the moving body by a dead reckoning operation while a front-steering-wheel movement amount, a front-steeringwheel steering angle, a rear-steering-wheel movement amount, a rear-steering-wheel steering angle, a posture-angle change amount and the wheel-base length of the moving body are used. When the judgment judges that the moving body is swiveled and moved, the slewing radius of a measuring point which is set on a wheel base is found by using the front-steering-wheel movement amount, the rear-steering-wheel movement amount, the posture-angle change amount and the wheel-base length while the moving body is swiveled and moved. The position of the moving body is measured on the basis of the movement amount during the swiveling motion calculated from the found slewing radius and the found posture-angle charge amount.