Ocean acidification and eutrophication are two prominent problems that affect marine ecosystems in manyaspects. Ocean acidification affects a series of physiological activities of macroalgae, which serve as important primaryproducers in marine ecosystems with regard to growth, photosynthetic carbon, and nutrient absorption. Moreover, it isglobally acknowledged that seaweed cultivation is an effective way to ease the pressure of offshore eutrophication. (Rhodophyta, Rhodophyceae, Florideophycidae, Gigartinales, Gracilariaceae) is distributed inwarm water along the coast of Zhejiang and Fujian Provinces. It grows in stone bogs in the intertidal zone, andsandstone and shells in the subtidal zone. –40 cm long with a rufous color andcylindrical fronds. The ecological effects of has been used toimprove pond water quality, because it absorbs N and P when it is growing. Moreover, it shows high economic value asboth raw agar material and abalone feed. The majority of research on has been about pond cultivationtechniques, growth, uptake of nutrient and biochemical composition, and ultrastructure of vegetative cells. However,there are few reports on the interaction effects of C and N on its eco-physiological characteristics. This studyinvestigated the growth and biochemical composition of in response to different C sources (a model of oceanacidification) and N sources (a model of eutrophication). was exposed to two C concentrations of 800 (enhanced) and 400 (as control),and four N concentrations of 100 μ-N (enhanced), and 10-N (as the control), with three replicates for each group. The culture density of was 1 g/L. Thealgae were cultured under 100 s) illuminated by incandescent tubes for 12L : 12D photoperiod at 20.The culture seawater was continuously aerated and renewed every 2 days. Differences in seaweed growth, soluble sugar(SS), soluble protein (SP), phycoerythrin (PE), chlorophyll a (Chla), total nitrogen (TC), and total carbon (TN)were measured 10 days after being exposure to different conditions. The results indicated that enhanced C and Nwere proposed to increase seaweed growth, and the special growth rate reached its peak (11.70%/d) in the 800 and 100 -N treatments. Moreover, high COlevels induced decrease of SP, PE, and Chla contents,whereas SS content increased. With density increase of NaNO, PE and SP gradually increased, SS gradually reduced,and Chla had no significant change (growth and directly affects its physiological and biochemical characteristics. The growth rate of can be considered a suitable bioremediation speciesfor artificial culture in regions that experience eutrophication.