The predissociation of H 2 in its Rydberg states has been studied using the multichannel quantum defect theory,combined with the frame transformation and the non iterative eigenchannel R matrix method.The predissociation line positions and the widths are calculated for 3pπ 1πu+(v=3,J=1,2) and 4pσ B″1Σu+(v=2,J=1,2) levels.The predissociation mechanisms are discussed.