With the goal of solar sail mission to near interstellar space (200AU) in 20 years, a global optimization problem of solar sail gravity assist and solar photonic assist trajectory for interstellar mission was studied. A mathematical model for solar sail time-optimal trajectory was established. By taking the constrains of solar sail gravity assist and solar photonic assist into the object function, the four-point boundary value problem of orbit optimization can be converted to multi-variable optimization problem of no constraint. With choosing appropriate constrain proportions, the problem was solved by using genetic algorithm and sequential quadratic programming method. Optimization result shows that plenty of time can be saved by adding Jupiter gravity assist, though solar sail gains a large velocity with solar photonic assist. The proposed global optimization algorithm will provide a reference for the preliminary design of solar system escape orbit.