Glutaredoxin 2 (Grx2) from Escherichia coli is larger in size than classical glutaredoxins. It is extremely efficient in the catalysis of reduced glutathione-dependent disulfide reduction. A complex of Grx2 with reduced glutathione (GSH) has been crystallized. Data were collected to 1.60 A. The crystals belong to space group P3(2)21, with one Grx2-GSH complex in the asymmetric unit. The unit-cell parameters are a = b = 50.10, c = 152.47 A. A Grx2 mutant, C9S/C12S, which cannot form a disulfide bond with GSH was also crystallized. The crystals diffracted to 2.40 A and belong to space group P2(1)2(1)2(1), with one molecule in the asymmetric unit. The unit-cell parameters are a = 28.16, b = 78.65, c = 89.16 A.