Abstract A new high temperature superconducting (HTS) cable project supported by the Ministry of Economy, Trade and Industry (METI) and the New Energy and Industrial Technology Development Organization (NEDO) has just started in Japan. This project targets operation of a 66 kV, 200 MVA HTS cable in the real grid in order to verify its reliability and operation performance. The Tokyo Electric Power Company (TEPCO) provides the real grid and studies the influence of connecting the HTS cable. Sumitomo Electric Industries, Ltd. (SEI) manufactures the HTS cable, terminations and joint. Mayekawa Mfg. Co., Ltd. provides the cooling system. This project consist of the design of a total system to be finalized in 2008, the manufacture of the cable, terminations and joint scheduled for completion in 2009, installation in spring and summer of 2010 and commissioning by the fall of 2010. The HTS cable will be connected to the real grid in the 154/66 kV substation. It is set up between the 154/66 kV transformer and the 66 kV bus line. This report shows the outline of this project and details of the influence of the connecting cable to the real grid.