In order to increase the macroalgae resources, the Sargassum spp. were chosen as target species for forestation and restoration experiments in the ocean. After transplantations, the growth rates and survival rates of Sargassum spp. were best in Erkan, Watung the second and Chinwan the worst. Thoroughly investigations on the growth cycles and distributions help to know the life histories, environmental demands and even the ways to preserve the species resources of Sargassum spp. Simple methods were established for thallus regenerations from holdfasts, stipes and blades of brown alga Sargassum spp., and determination of suitable media. Seven species of Genus Sargassum were collected at the intertidal zones of Si-wei, Guanyinting, Wukan, Chin-Wan, Her-Chieh, Wa-Tong, Er-Kan and Chi-Ma in Penghu from January to October, 2007. The holdfasts, stipes and blades of Sargassum spp. were cultivated with agar media, and the result showed that regenerate rates of holdfasts of S. polycystum, S. hemiphyllum var. chinense and S. polycystum could reach 100%. Furthermore, the above three species were cultivated with four different media: agar, purified agar (A 1296), high gel strength agar (A9799) and carrageen (C1013) after being immobilized with algin. Regeneration rates of all combinations of treatments and samples also reached 100%. It suggested that holdfasts of Sargassum spp. could be excellent candidates for artificial seeds. Photosynthesis of macroalgae helps to absorb carbon dioxide. The results also show better efficiency of absorbance than microalgae.