To prepare spray-drying precursor nano-Al suspension with good dispersion stability, nano-Al suspension was prepared by mechanical stirring and ultrasonic dispersion, and the dispersion stability of nano-Al in RDX solution was investigated. Based on the measurement of ultraviolet spectrophotometer, the effects of dispersion rate, dispersion time, ultrosonic time, temperature and nano-Al particle size were systematically studied. The microphology structure of spray-drying samples were analyzed by scanning electron microscopy. The results showed that the aluminum powders with particle size of 50-100 nm, the best dispersion stability was achieved at the following conditions: stirring rate of 400 r·min^-1, dispersion time of 30 min, ultrasonic time of 3-10 min, suspension concentration of 1%, temperature of 25 ℃.