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This paper describes numerical simulations of the typical hovering mode of dragonfly wings with different sweeping motions. The simulation process involves solving the three-dimensional unsteady Navier–Stokes equations and exploring the effects of the sweeping motion on aerodynamic performance. Various parameters related to the three-dimensional sweeping motion are studied, including the sweeping amplitude, phase difference between flapping and sweeping motions, asymmetry of sweeping amplitudes of the forewing and hindwing, and frequency of sweeping motion. The results show that as the sweeping amplitude of the forewing and hindwing increases from 0 to 35°, the time-averaged lift and the lift efficiency increase by ∼4 times and ∼3.6 times respectively, while the power consumption first decreases and then increases. Moreover, increasing the sweeping amplitude delays the shedding of the trailing edge vortex. A phase difference of ∼60° between flapping and sweeping maximizes efficiency and the change in phase difference can lead to vertical forces in opposite directions on the forewing and hindwing. Accordingly, the flow field interference between the two wings will be more serious. Greater symmetry between the sweeping amplitudes of the two wings leads to better lift performance. There is an optimal sweeping frequency which is also the same as the flapping motion, representing an elliptical trajectory that can make lift ∼0.75 times higher. The optimal combination of various sweeping motion parameters may contribute to better aerodynamic performance in the hovering state. This research provides theoretical guidance for the design of dragonfly-like aircraft with multiple degrees of freedom. [ABSTRACT FROM AUTHOR]