In the present research,the effects of temperature and illumination intensity in liquid preservation as well as the water content of the beads in encapsulation cryopreservation on the preservation of the filaments of S.lomentaria were studied,mainly to find out some appropriate techniques and the optimal situations to realize the effective preservation of germplasm of S.lomentaria.The filaments of S.lomentaria were preserved under various temperature and illumination intensity in the incubator for 60 days in liquid preservation.In encapsulation cryopreservation,filaments of S.lomentaria were stored in -20℃ refrigerator for 30 days after being encapsulated into the beads and dehydrated with silica gel.The experimental results showed that:(1)In liquid preservation,temperature was not the key factor on the preservation of the filaments of S.lomentaria,and the filaments of S.lomentaria could achieve long-term preservation under the condition of 5.4 μmol/(m²·s),6-18℃;(2)The illumination intensity had a significant impact on the liquid preservation of the filaments of S.lomentaria,any illumination intensity higher than 16.2 μmol/(m²·s)was not conducive to the preservation of the germplasm,5.4 μmol/(m²·s)was the most helpful condition;(3)After being preserved at 6-12℃,and 5.4 μmol/(m²·s)for 60 days,the cells of the filaments of S.lomentaria were still in good condition and the survival rates were higher than 97%;(4)The survival rates of the filaments of S.lomentaria after encapsulation cryopreservation were reduced whether the water content of the beads was too high or too low,and 15% was the optimal water content at which the survival rate of the filaments of S.lomentaria preserved for one month could still be higher than 50%.The research demonstrated that,in appropriate situations,filaments of S.lomentaria could be successfully preserved both by the methods of liquid preservation and encapsulation cryopreservation.