We have isolated and characterised three barley cDNAs encoding glutathione peroxidase (GPX) homologues, designated HVGPH1, HVGPH2 and HVGPH3. HVGPH1 may represent a cytosolic form of GPX. The structure of the HVGPH2 N-terminal domain is typical for a plastid transit peptide. A potential peroxisomal targeting sequence occurs near the N-terminus of HVGPH3. Transcript levels of HVGPH1 and HVGPH2 were increased in leaves undergoing stress. In contrast, HVGPH3 mRNA accumulation showed a negative response to stress. Our data indicate that the barley genome bears a small gene family encoding GPX homologues differing in their function and cellular localisation.