It was found that hydrogen was produced from 1,4-dihydronicotinamide derivatives such as 1-benzyl-1,4-dihydronicotinamide (BNAH) and 1-n-propyl-1,14-dihydronicotinamide (PrNAH) in the presence of colloidal Pt as a catalyst. The reaction proceeded heterogeneously in the case of BNAH because it is insoluble in water. Hydrogen generation was two-fold greater than in pure water when the mixed solvent water-methanol was used instead of pure water in order to carry out the homogeneous reaction. Further, ca. ten-fold as much hydrogen was produced in the case of water-soluble PrNAH, compared with BNAH. The effect of alloxans, such as alloxan (A) and N, N prime - dicyclohexylalloxan (DCA), as electron transfer catalysts (ETC) on hydrogen generation by use of BNAH or PrNAH was examined. It is observed that the rate of hydrogen production was increased by adding alloxans, and the amount of the evolved hydrogen in the case of PrNAH increased about ten-fold by the addition of A.