GaAs0.9Sb0.1 epilayer is grown by two growth models of liquid phase epitaxy technique, and the two models are step-cooling and super-cooling, respectively. The crystal structure, cross-sectional image, and luminescence property of GaAs0.9Sb0.1 epilayer are studied with utilization of X-ray diffractometer, scanning electron microscope, and Raman spectometer. The results show that the growth rate of GaAs0.9Sb0.1 epilayer grown with step-cooling is slower than that with super-cooling, and GaAs0.9Sb0.1 epilayer grown by step-cooling exhibits higher-quality crystalline structure and smoother interface. However, the GaAs0.9Sb0.1 epilayer grown by the two growth models display substantially similar photoluminescence property.