Stirling engines are the composition of 2 pistons in 2 cylinders or 2 pistons in 1 cylinder except for a double acting type engine. Heater, regenerator and cooler are installed between 2 pistons. In the meantime, the pulse tube engine consists of 1 piston in 1 cylinder, pulse tube, heater, regenerator, cooler and 2^<nd> cooler. Therefore, the composition resembles the Stirling engine well. However, the composition of the engine is more simplified than the composition of the Stirling engine. And, the piston and cylinder are in a room temperature environment. So, the heat measure is unnecessary for sealing mechanisms such as a piston ring. In this paper, using the energy flow on the thermodynamics, the examination which develops the pulse tube engine based on the working principle of the pulse tube refrigerator is carried out. In order to investigate the basic characteristics of the pulse tube engine, an engine of simple composition, which used atmospheric pressure air in the working gas, has been manufactured. Effects of the orifice, bypass and inertance on shaft power are examined experimentally. As the result, the excellent effect of the inertance has been confirmed. The feasibility of the pulse tube engine has been verified thermodynamically and experimentally.