We proposed a new motion vector (MV) smoothing using fuzzy weighting and vector median filtering for frame rate up-conversion. A fuzzy reasoning system adjusts the weighting values based on the local characteristics of MV field including block difference and block boundary distortion. The fuzzy weighting removes the affect of outliers and irregular MVs from the MV smoothing process. The simulation results show that the proposed algorithm can efficiently correct wrong MVs and thus improve visual quality of the interpolated frames better than conventional methods.