In this paper we report an investigation about the relationship between Bi content and conductivity for the La10-xBix(SiO4)(6)O-3 (x = 0.5-2) specimens. Increasing Bi content in apatite-type La10-xBix(SiO4)(6)O-3 specimen leads to increasing the average grain size and sinterability because some Bi ion deposited at grain boundaries which promotes grain growth. The relative sintered density of the La8Bi2(SiO4)(6)O-3 specimen is 98%. There is a small shift in diffraction angle of XRD peaks, complicated lattice distortion was observed in the X-ray pattern with increasing content of Bi. Electrical conductivity of La10-xBix(SiO4)(6)O-3 specimen increased with increasing Bi contents and the value of the La8Bi2(SiO4)(6)O-3 specimen is 2.4 x 10(-4) S cm(-1) at 700 degrees C. (C) 2012 Elsevier Ltd. All rights reserved.