Error analysis is carried out to test the variational model of synthetic aperture radar sea surface wind retrieval. On condition that the background error is maximum, the analysis error is lower than the background error, and with the increase of the background wind direction, the analysis error changes periodically; on condition that the background error gradually increase, the analysis error increases gradually and its deviation direction coincides with the background error deviation direction; under the condition of specific background field, the variational model is compared with the direct inversion model: when the background wind speed is low, the variational model error is slightly high, when the background wind speed is high, the variational model error is significantly low. Generally, the variational model wind speed error is less than 1.60 m/s, and the wind direction error is less than 17.15°, which are better than those of the direct inversion model.