Eight lupin (Lupinus angustifolius L.) genotypes grown at four locations in south central Alberta in 2004 were evaluated for variability in phenolic constituents and antioxidant activity measured by a photochemiluminescence assay. Genotype was the main source of variation for content of phenolic compounds and antioxidant activities. Phenolic compounds in genotypes varied minimally from 11.9 to 14.7 mg catechin equivalent and 4.15 to 4.95 mg rutin equivalent g(-1) lupin for total phenolic and flavonoid contents, respectively. Lupin genotypes exhibited weak antioxidant activity based on water-soluble substances (ACW) of 0.54 to 1.07 micromole Trolox equivalent antioxidant capacities (TEAC)/g with lag time ranging from 70 to 153 s and an antioxidant index of 6.7 to 14.5 and 1.9 to 3.3 micromole TEAC/g based on measurements of lipid-soluble substances (ACL). Antioxidant activity of lupin genotypes was not related to phenolic contents of seeds.