Through a consideration of the requirements for a DEMO-relevant blanket concept, Korea (KO) has proposed a He Cooled Molten Lithium (HCML) blanket with Ferritic Steel (FS) as a structural material in the International Thermonuclear Experimental Reactor (ITER) program. The design and WKH performance of the KO HCML Test Blanket Module (TBM) are introduced in this paper. It uses He as a coolant at an inlet temperature of 300°C and an outlet temperature up to 406°C and Li is used as a tritium breeder by considering its potential advantages. Two layers of graphite are inserted as a reflector in the breeder zone to increase the Tritium Breeding Ratio (TBR) and the shielding performances. A 3-D Monte Carlo analysis is performed with the MCCARD code for the neutronics and the total TBM power is designed to be 0.675 MW at a normal heat flux from the plasma side. From the analysis results with CFX-10 for the thermal-hydraulics, the He cooling path is determined and it shows that the maximum temperature of the first wall does not exceed 550 °C at the structural materials and the coolant velocities are 50 m/sec and 25~32 m/sec at the first wall and breeding zone, respectively. The obtained temperature data is used in the thermal-mechanical analysis with ANSYS-10. The maximum von Mises equivalent stress of the first wall is 2540 MPa and the maximum deformation of it is 1.3 mm.