An in-vehicle processing apparatus is capable of performing position estimation resistant to disturbance. The in-vehicle processing apparatus includes: a storage unit that stores point cloud data including a plurality of coordinates of a point representing a portion of an object in a first coordinate system; a sensor input unit that acquires an output of a sensor that acquires information regarding vicinity of a vehicle; a movement information acquisition unit that acquires information related to movement of the vehicle; a local periphery information creation unit that generates local periphery information including a position of the vehicle in a second coordinate system and a plurality of coordinates of a point representing a portion of an object in the second coordinate system on the basis of information acquired by the sensor input unit and the movement information acquisition unit; and a position estimation unit that estimates a relationship between the first coordinate system and the second coordinate system on the basis of the point cloud data and the local periphery information and then estimates the position of the vehicle in the first coordinate system.