The flatus‐producing factor in soybean [Glycine max (L.) Merrill] seed appears to be associated with the sugars raffinose and stachyose. The objective of this investigation was to measure the variability of total sugar and individual sugars in seed from soybean cultivars, the soybean genetic type collection, plant introductions of G. max that were formerly known as G. gracilis Skvortz., and plant introductions of G. soja Sieb. and Zucc.Among the cultivars, ‘Bansei’ had the highest total sugar, sucrose, and stachyose contents—16.6, 10.2, and 3.8 g/100 g seed, respectively. Seed of ‘Sioux’ had the lowest total sugar and sucrose contents—6.2 and 3.0 g/100 g seed. Seed of ‘Chippewa’ and ‘Norsoy’ had the highest and lowest fructose contents—2.1 and 0.4 g/100 g seed, respectively. Raffinose content was highest in seed of ‘Cayuga’ and lowest in ‘Hidatsa’ and Sioux. Strains T‐223 and T‐218 in the genetic type collection had very high stachyose contents—5.8 and 4.8 g/100 g seed. In seed of G. soja PI 203.246, the stachyose content was only 0.6 g/100 g seed.The extent of variability detected for total sugar and individual sugar content offers opportunities for modification of the sugar components in soybeans.