This paper presents the results of SHS Of beta-Si3N4 whiskers from silicon powders with alpha-Si3N4 as diluents under high nitrogen pressure. The effect of the addition of different amounts Of Y2O3 on beta-Si3N4 whisker synthesis has been investigated in detail. The results revealed that Y2O3 dditive had a marked effect on the growth Of beta-Si3N4 whiskers compared that without additives. The optimum amount Of Y2O3 addition is from 2.4 to 4.8 wt.%. (C) 2002 Elsevier Science Ltd. All rights reserved.