In order to reduce fuel consumption and exhaust emissions caused by frequently starting and idling vehi-cles at signalized intersections,the problem of eco-driving strategy at signalized intersection on energy-saving oriented is studied.With the help of the V2I communication system in intersection areas,GPS locations and moving states of vehi-cles,also signal phase and timing information are obtained,then optimal speed advisory scenarios of green lights are de-termined according to these data.Time and space trajectories of vehicles under each scenario are analyzed.Considering fu-el consumption of upstream and dow nstream areas of intersections,a unified optimization objective function is established with a goal of minimum average fuel consumption per kilometer.The optimal solution of eco-driving strategy is obtained, and speed advice is provided to the driver.A random simulation is carried out by Matlab.It shows that the eco-driving strategy can reduce fuel consumption by more than 10% comparing with non-eco-driving speed strategy.Among the six green light optimal speed advisory scenarios,the most significant fuel saving of the optimal eco-driving strategy appears in Case 2,which reaches 30% -60%,followed by Case 4,which reaches 25% -50%.It appears slightly worse in Case 3 and Case 5.In order to improve fuel consumption efficiency,vehicles should avoid stopping and waiting when passing sig-nalized intersections.They can also try to pass through intersections by appropriate acceleration and deceleration if necessary.