An easily segregated adsorbent for highly efficient removal of mercuric (Hg(II)) ions from aqueous media remains a great challenge. Herein, A novel Fe3O4@MoS2 core-shell magnetism nanocomposite with rich sulfur in the shell was fabricated through a facile in-situ hydrothermal method, which has high adsorption efficiency and good selectivity for Hg(II) ions and can be easily removed by magnetic separation. Thus, Fe3O4@MoS2 can act as a potential adsorbent for highly efficient removal of Hg(II) ions from aqueous media.