英：Hummingbirds are versatile natural flyers that can perform locomotion as insects, such as hovering, forward/backward flight, turning maneuver and more. The unsteady vortex dynamics is key to understand aerodynamic features of these motions. Here we present an integrated approach combining high-speed photogrammetry, wing/body surface tracking, and immersed boundary method based flow simulations to study the three-dimensional vortex dynamics of a freely maneuvering hummingbird. The simulation results of the hummingbird performing pure yaw turn show asymmetric wake structures between the inner and outer wings. Dual-loop vortex structures have been observed in the near wake of the outer wing during downstroke, and of the inner wing during upstroke. The interactions between the wings and these complex vortex structures have implied both aerodynamic and dynamic benefits of the flapping wings in hummingbird’s maneuvering flight.