Composite insulators have a number of advantages over porcelain insulators, including lighter weight, better contamination performance and explosion resistance, and easier construction. They are therefore being considered for use with outdoor terminations for XLPE cable especially for those installed on pylon branching. Tokyo Electric and Furukawa Electric have jointly developed 66 kV and 154 kV outdoor terminations with composite insulators. This article presents the primary advantages of the composite insulator and the electrical performance of the termination for XLPE cable using composite insulator instead of a porcelain one. Also, the specification of the 66 kV and 154 kV composite insulator terminations applied to the Tokyo Electric Power's Oihama Line and Koai Line are introduced.