Double － circuit ± 800 kV UHVDC transmission project in the second phase of Jinsha Ｒiver project of State Grid are planned and constructed in the year of 2021 ～ 2025． According to the hydrologic output characteristics of Baihetan hydropower station and the substantial surplus of Sichuan green clear energy in the year of 2021 ～ 2025，and combined with the characteristics and advantages of double － circuit ± 800 kV UHVDC transmission project in the second phase of Jinsha Ｒiver project， the measures for improving UHVDC delivery output in the second phase of Jinsha Ｒiver project are proposed． The research results show that: by taking the measures，the quantity of abandoning energy in high flow period of Sichuan power grid can be decreased about 5000 GW·h and the annual utilization hours of double － circuit ± 800 kV UHVDC transmission lines in the second phase of Jinsha Ｒiver project can be increased about 470 hours．