Although there has been no commercialization of supercritical carbon dioxide (SCO2) power generation technology globally, lots of efforts are underway because of its potential enhancement in compactness and efficiency. Korea Institute of Energy Research (KIER) has been developing three SCO2 turbines and two test loops, since 2013. KIER recently built and tested an axial SCO2 turbine generator, which is the world's first attempt as an axial type in the area of SCO2 technology. SCO2 turbines are characterized by miniaturization and high-speed rotation due to its high density. These increase the degree of technical difficulty significantly in the management of axial force and windage loss which are generated by the rotor and cause mechanical loss or damage of rotating parts in the turbine. In contrast to previous studies, KIER designed the turbine as an axial impulse type to reduce the axial force and introduced a mechanical seal and leakage management system to reduce windage loss. Initial test results showed that the turbine can be operated at the inlet conditions of 205℃/100 bar. The maximum power output of 11 kWe was obtained at the running speed of about 20,000 rpm.