To enhance the reactivity and energy release efficiency of aluminum powder fuel， ammonium perchlorate （AP）-coated micro/nano composite aluminum powder was prepared via a liquid-phase deposition-spray drying method. Scanning electron microscopy （SEM）， calorific value measurements， Hartmann tube flame propagation tests， and high-speed infrared imaging were employed to systematically investigate the effects of the AP-coated micro/nano structure on combustion performance. The results indicate that， in the uncoated system， the sample with 18% nano-aluminum exhibited the most uniform particle surface distribution， achieving a calorific value of 31.3 MJ·kg^-1. In the AP-coated system， high reactivity was maintained even at elevated nano-aluminum contents， with the 24% nano-aluminum sample exhibiting a calorific value of 27.5 MJ·kg^-1. AP coating significantly increased the flame propagation velocity and advanced the peak occurrence time； for the 18% nano-aluminum sample， the maximum flame propagation velocity increased from 62.81 to 67.50 m·s^-1. Infrared imaging results indicate that AP coating reduces the peak flame temperature and shifts the high-temperature zone from edge-enhanced to centrally concentrated.