An object detection apparatus comprising: an input port adapted to receive target information including pieces of information, each piece of information being associated with a respective object of a plurality of objects in the surroundings of a vehicle and receive traffic information representing a traffic environment in the surroundings of the vehicle, the target information of the plurality of objects being detected by a sensor installed on the vehicle; a memory adapted to store the received target information and the received traffic information; a controller adapted to determine whether or not a total amount of data of the target information is greater than a determined value in order to determine whether the target information is able to be transmitted to an in-vehicle apparatus; in case where the total amount of data of the target information is greater than the determined value, determine, based on the target information and the traffic information, a priority to each of the plurality of objects, select pieces of information from the target information based on the priority; and an output port adapted to output the selected pieces of information to the in-vehicle apparatus that controls the vehicle, wherein the piece of information on each object detected by the sensor includes a plurality of items associated with the object, wherein the output port is adapted to output, to the in-vehicle apparatus, selected pieces of information classified in a first group and selected pieces of information classified in a second group such that selected pieces of information being high in priority are classified in the first group, and wherein a number of items included in the pieces of information in the target information classified in the first group is larger than a number of items included in the pieces of information in the target information classified in the second group. an input port adapted to receive target information including pieces of information, each piece of information being associated with a respective object of a plurality of objects in the surroundings of a vehicle and receive traffic information representing a traffic environment in the surroundings of the vehicle, the target information of the plurality of objects being detected by a sensor installed on the vehicle; receive target information including pieces of information, each piece of information being associated with a respective object of a plurality of objects in the surroundings of a vehicle and receive traffic information representing a traffic environment in the surroundings of the vehicle, the target information of the plurality of objects being detected by a sensor installed on the vehicle; a memory adapted to store the received target information and the received traffic information; a controller adapted to determine whether or not a total amount of data of the target information is greater than a determined value in order to determine whether the target information is able to be transmitted to an in-vehicle apparatus; in case where the total amount of data of the target information is greater than the determined value, determine, based on the target information and the traffic information, a priority to each of the plurality of objects, select pieces of information from the target information based on the priority; and determine whether or not a total amount of data of the target information is greater than a determined value in order to determine whether the target information is able to be transmitted to an in-vehicle apparatus; in case where the total amount of data of the target information is greater than the determined value, determine, based on the target information and the traffic information, a priority to each of the plurality of objects, select pieces of information from the target information based on the priority; and an output port adapted to output the selected pieces of information to the in-vehicle apparatus that controls the vehicle, wherein the piece of information on each object detected by the sensor includes a plurality of items associated with the object, wherein the output port is adapted to output, to the in-vehicle apparatus, selected pieces of information classified in a first group and selected pieces of information classified in a second group such that selected pieces of information being high in priority are classified in the first group, and wherein a number of items included in the pieces of information in the target information classified in the first group is larger than a number of items included in the pieces of information in the target information classified in the second group. output the selected pieces of information to the in-vehicle apparatus that controls the vehicle, wherein the piece of information on each object detected by the sensor includes a plurality of items associated with the object, wherein the output port is adapted to output, to the in-vehicle apparatus, selected pieces of information classified in a first group and selected pieces of information classified in a second group such that selected pieces of information being high in priority are classified in the first group, and wherein a number of items included in the pieces of information in the target information classified in the first group is larger than a number of items included in the pieces of information in the target information classified in the second group.