Abstract: A pneumatic hybrid electric engine includes an electric source, an air supply part for compressing air and storing the compressed air, a pneumatic engine part for generating power using air supplied from the air supply part, an electric engine part for generating power using electric power applied from the electric source, a power transmission part for transmitting the power generated by the pneumatic engine part and the electric engine part, and a control part for selectively operating the pneumatic engine part and the electric engine part so that the pneumatic and electric engines parts can be switched on the basis of a predetermined torque range.