To investigate the flow characteristics of an aviation jet oscillator, a high-frequency aviation jet oscillator was designed. The frequency-pressure response characteristics, velocity-pressure response characteristics, and internal flow characteristics were studied experimentally and numerically using high-frequency dynamic pressure sensors and two-dimensional unsteady numerical simulation methods. The research results show as follows. In a jet oscillator with given geometric dimensions, the pressure oscillation frequency at the jet nozzle is twice that at the feedback loop. Within a certain range, as the inlet-to-outlet pressure ratio increases, the oscillation amplitude of the jet oscillator also gradually increases. Within a certain range, as the inlet flow rate increases, the jet oscillation frequency increases linearly. These findings provide important academic and engineering guidance for the design and application of jet oscillators, helping engineers better understand and control the performance of such devices to meet the needs of various aviation applications.