The effect of excess PbO(0, 3, and 8mol%) on grain growth of relaxor ferroelectric (65)Pb{{{{ { { Mg}_{1/3 }Nb }_{2/3 } {O }_{3 } }}-(35){{{{ { PbTiO}_{3 } }} (mol%) ceramics has been investigated. When the (65)Pb{{{{ { { Mg}_{1/3 }Nb }_{2/3 } {O }_{3 } }}-(35){{{{ { PbTiO}_{3 } }} samples containing excess PbO(3 and 8 mol%) were sintered at 120$0^{circ}C$ with atmospheric powder (lead zirconate) abnormal grain growth occurred. After the sintering for 120 h the abnormal grains grew up to about 1 mm and covered almost all of the sample surface especially in the sample with excess 3 mol% PbO. The number of abnormally grown grains per unit area was higher in the sample with excess 3 mol% PbO but their size was bigger in the sample with excess 8mol% PbO. In the samples without excess PbO however the ab-normally grown grains were not observed. The abnormal grain growth int he sample with excess PbO was explained to result from the change of interface characteristics from rough interface to smooth interface by addition of excess PbO