The mechanical properties and creep resistance of the Al 2 O 3 have been improved with the use of other oxide ceramics, among these the Y 3 Al 5 O 12 (YAG - " yttrium aluminum garnet "), to obtain the Al 2 O 3 -YAG composite. The aim of this work is to study the effect of addition of Nb 2 O 5 at low sintering temperatures of the composite, starting from the eutectic composition Al 2 O 3 -Y 2 O 3 . In this work, the compositions were produced by powder mixtures of Al 2 O 3 -Y 2 O 3 and Al 2 O 3 -Y 2 O 3 -Nb 2 O 5 using high energy ball milling. The green bodies were pressed at 70 MPa and sintered at 1000, 1100, 1200 and 1300°C for 2 h. The materials were characterized by shrinkage and X-Ray Diffraction (XRD) using the Rietveld method. The presence of Nb 2 O 5 does not show any improve neither for the YAG phase formation nor for the shrinkage of the sintered samples in the temperature range studied.