For investigating the fuel spray characteristics of the nozzle designed for the aero-engine, the off-axis particle field holographic measuring system is used on an engine test-bed. The spray structure, atomized particles locations, amounts, and sizes distribution in space under different experimental conditions are obtained quantitatively. Experimental results show that under normal temperature and pressure conditions, the atomization field formed by this type of nozzle is distributed in a hollow cone. The atomized particles are concentrated on the surface of the cone. The diameter of the particles is mostly between 60 μm and 80 μm, with the distance from the nozzle increases, the particle diameter decreases and approaches the same, showing a uniform atomization effect. When the injection pressure is low, a vortex ring similar to the mainstream ring appears downstream of the dense vortex ring near the nozzle area. As the injection pressure increases, the number of vortex rings near the nozzle is reduced, the ripples and filaments of the liquid film are increased, and the mainstream ring is not observed downstream. The atomization structure on both sides of the jet is not completely symmetrical. Under the working conditions of 800 K and 5.5 kPa high temperature pure air flow, the average diameter of atomized particles in the combustion chamber is reduced to about 12 μm, and the atomization quality is significantly improved.