A hydrogen combustion turbine system has been proposed by Mitsubishi Heavy Industries, LTD. which is the Closed Circuit Cooled Topping Recuperation Cycle (CCCTR cycle) and is part of a Japanese government sponsored program WE-NET (“World Energy Network”). This cycle is composed of closed Brayton and Rankine cycles. The efficiency of this cycle is more than 60% HHV (Higher Heat Value) with a power capacity of 500MW. This cycle was selected as the most suitable for hydrogen combustion turbine used for industrial power plant by the Japanese government. A closed circuit steam cooling system has been proposed to cool vanes and blades of the high temperature turbine (HIT) which has inlet temperature of 1700°C and inlet pressure of 45bar. This paper presents the comparisons of the thermal efficiency and the feasibility of components between the CCCTR cycle and other cycles.