Antioxidant activities of canola protein hydrolysates (CPHs) and peptide fractions preparedusing five proteases and ultrafiltration membranes (1, 3, 5, & 10 kDa) were investigated. CPHs hadsimilar and adequate quantities of essential amino acids. The effective concentration that scavenged50% (EC50) of the ABTS*+ was greatest for the <1 kDa pancreatin fraction at 10.1 ÃŽÂ¼g/ml. CPHs andpeptide fractions scavenged DPPH*+ with most of the EC50 values being <1.0 mg/ml. Scavenging ofsuperoxide radical was generally weak, except for the <1 kDa pepsin peptide fraction that had a valueof 51%. All CPHs inhibited linoleic acid oxidation with greater efficiency observed for pepsinhydrolysates. The oxygen radical absorbance capacity of Alcalase, chymotrypsin and pepsinhydrolysates was found to be better than that of glutathione (GSH) (p<0.05). These results show thatCPHs have the potential to be used as bioactive ingredients in the formulation of functional foodsagainst oxidative stress.