The invention discloses design and preparation method of a nano mercury-removal material taking a mussel shell as a raw material. The method comprises the following steps that typical mussel shells are collected; characterization analysis is carried out on mussel shell samples to establish a mussel shell database; modified treatment is carried out on the mussel shell samples; according to the mixing ratio of various mussel shell materials, a variety of nano mercury-removal material formulas are designed; the various mussel shell materials are mixed according to proportions according to the formulas to prepare the nano mercury-removal material; the mercury adsorption capacity of the nano mercury-removal material is tested, and the nano mercury-removal material is evaluated and screened; andthe nano-mercury material is characterized in situ. The design and preparation method of the nano mercury-removal material taking the mussel shell as the raw material have the advantages that the fire coal Hg control technology and environmental treatment material research are combined to provide a fire coal flue gas mercury-removal material taking the mussel shell as the raw material, thereby contributing to promoting comprehensive utilization of coastal solid wasted mussel shell resources, realizing waste treatment with processes of wastes against one another and developing a circular economy.