Abstract: A measurement apparatus unit is mountable to a vehicle. The measurement apparatus unit includes a first sensor, a first storage apparatus, and a first relay. The first sensor is arranged in a first area among a plurality of areas that are segmented in advance in the vehicle. The first storage apparatus stores therein detection data that is acquired from the first sensor. The first storage apparatus is arranged in a second area that differs from the first area among the plurality of areas. The first relay communicably connects at least the first sensor and the first storage apparatus. The first area and the second area are separated from each other in a traveling direction of the vehicle.