The silverleaf whitefly (SLW), Bemisia tabaci B-biotype was first discovered in Australia in 1994 (Gunning et al , 1995). This biotype is a major pest of cotton and other crops in many overseas counties and is a considerable threat to cotton in Australia. Another indigenous biotype of B. tabaci (IBW), that is not considered a pest, is common in Queensland. This paper reports the results of sampling for these biotypes in the cotton areas of Queensland during the past two years'