Eco-operation with ocean current forecast information leads to energy-saving because it increases the speed over ground and enables less fuel consumption. In 2018, we carried out the Eco-energy project which is subsidy project by Agency for Natural Resources and Energy. In this project, we provided ocean current forecast information to 76 domestic vessels via a tablet, and the captain utilized this information to attempt energy-saving operation. This paper proposes a regression model with statistical test to evaluate the effect of energy-saving operation using ocean current forecast information. As a result, 4 out of 5 ships had an energy-saving operation effect, leading to a fuel efficiency improvement of about 2%.