Abstract: Five types ofartificiallydesigned suhstrata(oyster shell,meretrix shell,small rock,small tile and smallgranite stone)adhered with discoidcrusts of Gracilaria asiatica were cultured ina degenerate seaweed bed locatedin the intertidal zonesof Xiaodeng Island,Xiamen,Fujian Province,from April to December,2011.The efects ofgermlng gnowth were comparativelyanalysed after summer season.The results showed that algal germlings atachedon the substrata of oyster shell had the lowest growth density and survival rate.Additionally,the gemlings wereeasily brushed off by the sea waves leading to just a few fronds gowing on thesurface of meretrix shell,small rockand small tile.However,the small granite stone presented the optimum effect of germling attachment.The growthdensity and survival rates were 3.77~15.95 and 2.02~4.56 times higher than those of other substrata after sum-merseason,respectively(p<0.05).Subsequently,6 groups of different sizes of small granite stones were statisti-cally analysed for gemmling growth from Aprial of 2012 to January of 2013.It showed that the germlings had similardensities on the surfaces of small gramite stones before summer.But after summer both the smallest size stones(-5 mm)and the largest size stones(+30 mm)had low attachments,low biomass and low survival rates of thegermlings.The stones with moderate size(+5 mm and -15 mm)showed significantly highest algal density,sur-vival rates and biomass,which were 1.64~10.56,1.28~2.51 and 1.39~2.26 times higher than those of othersize groups,respectively(p<0.05).It was suggested that small granite stones with moderate sizes were suitableartificial substrata for the remediation of Gracilaria asiatica on the seaweed bed.