An electricity generating apparatus capable of efficiently and safely charging a storage battery in an unmanned aerial vehicle during its flight and an unmanned aerial vehicle equipped with such apparatus. The apparatus is mounted in the vehicle, including a fuel tank which is a container body to reserve fuel, an electric generator unit connected to the fuel tank, tilt measurement means capable of measuring a tilt of the fuel tank, and electricity generation control means for controlling operation of generating electricity by the electric generator unit, wherein the electric generator unit is capable of charging a storage battery in the vehicle during flight, and the electricity generation control means drives the electric generator unit when a tilt angle of the fuel tank indicated by the tilt measurement means is within a safe angle which is a predetermined threshold angle, as well as an unmanned aerial vehicle equipped with such apparatus.