The compounds of FeO-V2O5 binary system were analyzed through X-ray diffraction experiment.The thermodynamic data of these compounds and solution model were investigated by theoretical calculation,and the phase diagram was validated by DSC and XRD experiments.The phase diagram is composed by three eutectic reactions and two intermediate compounds of Fe2VO4 and FeVO4.The calculated results of FeO-V2O5 binary phase diagram are close to the experimental results from XRD and DSC.