A small low-cost UAV named "Ant-Plane UAV" has developed. It is intended to be used in Antarctica mainly for preliminary route investigation for ground expedition by taking aerial photographs or movies. The UAV system is required to be operated by nonspecialists in low temperature environment down to -20 degrees Celsius. It is also required to carry camera system and to fly more than 100km for route investigation. Development of the hardware and software of an autonomous flight control module and ground station software are emphasized, while off-the-shelf products which meet temperature requirement are used as much as possible for most of the parts to keep the development cost low. This paper shows details of the Ant-Plane UAV and the results of the preliminary demonstration flights in Japan.