Low temperature sintering of PZT powders was investigated using Pb 5 Ge 3 O 1 1 (PGO) as a sintering aid. PZT powders with 150nm particle size were coated with PGO which was prepared from precursor solutions of Ge(OiPr) 4 and Pb(NO 3 ) 2 by sol-gel method. 1wt% PGO-added PZT powders were densified at 750 o C for 2h to sintered bodies with the relative density of approximately 95%. An addition of PGO improved the sinterability of PZT powders with a reduction of sintering temperature by about 300 o C. Dielectric and piezoelectric properties of PGO-added PZT ceramics sintered at 950 o C were superior to those without PGO additives. However, a higher sintering temperature above 1000 o C deteriorated the dielectric and piezoelectric properties of PGO-added PZT ceramics. This may be attributed to the change of microstructure involving the formation of solid solution between PZT and PGO. The 1wt% PGO-added PZT bodies sintered at 750 o C exhibited an electromechanical coupling factor, Kp, of about 56%.