The influence of sintering process on the density of nano-AgSnO2 composite was investigated using AgSnO2 powder prepared by electroless plating, adopting air sintering, hot pressing and vacuum sintering. The results show that density changed with compacting pressure, sintering temperature and sintering time when sintered in air, while the final density was close after repressing and resintering. For hot pressing, a density with higher than 96% could be achieved in a short time, but serious expansion and blistering ocurred. Vacuum sintering could help to wipe off adsorbates, but some residual still remained in the compact, and the expansion occurred during resintering. Low pressure compaction and step isothermal sintering could remove most of the adsorbates, and a high density of 94% was obtained after resintering. The large amount of absorbates on nano-AgSnO2 powder surface which led gases closed in the compact during sintering were found to be the main causes that affected densification process .