During the present project three different biosystems have been developed for the solar production of hydrogen. Three biosystems were : photoproduction of hydrogen by Rhodobacter sphaeroides O.U.001(DSM 5864), hydrogen gas production by using coupled enzyme systems of E.coli (DSM 1576) and Halobacterium halobiutn S9 and photoelectrochemical hydrogen production by Halobacterium halobium S9 . A suitable bioreactor have been designed and constructed for each biosystem. Results indicated that Rhodobacter sphaeroides O.U. 001 evolves hydrogen gas under anaerobic conditions and under illumination. The growth conditions such as pH, temperature, light intensity and cell concentration affected the hydrogen photoproduction. The recommended ranges of these parameters were pH 7,3 to 7,8. temperature 31 to 36 °C, light intensity 200 W / m2 and cell concentration between 1,6 to 1,8 mg dry weight / mL. The maximum photo production rate obtained was 0.047 L gas / hr / L culture (or 30 $mu$ moles hydrogen / min / L culture ) composed of 99 % hydrogen and 1 % carbon dioxide on argon free basis. It was found that anaerobic conditions were strictly required for hydrogen evolution by Halobacterium halobium S9 - E.coli coupled system. During anaerobic growth of E.coli 250 |imoles hydrogen / min / L culture of gas evolution was observed. The gas production rate was increased to 330 [$mu$ moles hydrogen / min / L culture with E.coli coupled to bacteriorhodopsin or packed cells of Halobacterium halobium . The evolved gas was composed of 98 % hydrogen and 2 % carbon dioxide on argon free basis. Growth curves of Halobacterium halobium S9 were obtained at different conditions. It has been observed that growth was faster at aerobic conditions with shaking. The photoactivity of packed cells did not change significantly in aerobic or anaerobic conditions, however, it was increased with increasing bacteriorhodopsin content. The results have indicated the enhancement wfv hydrogen production in the presence of light and Halobacterium halobium, compared to cell free photoelectrochemical reactor. This may be due to the biocatalytic effect of bacteriorhodopsin which is the photoreceptor protein of Halobacterium halobium. In this research molecular mechanics of bacteriorhodopsin were estimated by Hyperchem software and a new proton release and uptake mechanism has been proposed considering energy.