We describe here five kinds of defects found in Nd:YVO4 large crystals grown by the Czochralski method. These defects include: (1) color centers, (2) inclusions, (3) substructure, (4) uneven distribution of Nd3+ concentration and (5) processing stress. The mechanism of their formation and the methods of eliminating these defects are discussed. It is thought that the preparation of raw materials and stringent growing conditions are necessary to obtain high quality Nd:YVO4 crystals.