Among the different available wind sources, i.e. in situ measurements, numeric weather models, the retrieval of wind speed from Synthetic Aperture Radar (SAR) data is one of the most widely used methods, since it can give high wind resolution cell. For this purpose, one can find two principal methods: via electromagnetic (EM) models and empirical (EP) ones. In both approaches, the Geophysical Model Functions (GMFs) are used to describe the relation of radar scattering, wind speed, and the geometry of observations. By knowing radar scattering and geometric parameters, it is possible to invert the GMFs to retrieve wind speed. In this paper, wind speed retrieved by the two different models is compared together and evaluated with measured data. Based on the comparisons, some ideas will be proposed to improve the performance of wind speed retrieval.