Lactic acid fermentates of Chlamydomonas reinhardtii and Dunaliella tertiolecta biomass resulting from fermentation by a starch-hydrolyzing lactic acid bacterium, Lactobacillus amylovorus, were converted to H-2 by various photosynthetic bacteria. Using L. amylovorus and a halotolerant bacterial strain Rhodobium marinum, H-2 was produced at 8 mol/mol starch-glucose from C. reinhardtii biomass, while D. tertiolecta biomass, the H-2 production was 6 mol/mol starch-glucose even under the condition of 3% NaCl.