Thirteen species of sea lice (Copepoda, Caligidae) are described as parasites of marine fishes from Korea including three new species such as Pseudocaligus longipes n. sp. from Siganus fuscesens (Houttuyn), Lepeophtheirus tamladus n. sp. from Sebastes inermis Cuvier, and Lepeophtheirus gusevi n. sp. from Sebasetes schlegeli Hilgendorf. Remaining ten species are new to Korea: Caligus elongatus Nordmann, 1832; C. equulae Ho and Lin, 2003; C. fistulariae Yamaguti, 1936; C. laticaudus Shiino, 1960; C. rotundigenitalis Y$ddot{u}$, 1933; Metacaligus uruguayensis (Thomsen, 1949); Lepeophtheirus atypicus Lin, Ho and Chen, 1996; L. parvulus Shiino, 1952; Anuretes quadrilaterus Shiino, 1954; and Pseudanuretes chaetodontis Yamaguti, 1936.