Four taxa of the genus Chara L. (Charophyta), C. vulgaris L., C. sejuncta Braun, C. corallina Klein ex Willdenow var. kyusyensis Imahori and C. fibrosa Agardh ex Bruzelius var. microstephana Imahori are first recorded from Korea. Chara vulgaris, growing at the paddy fields and ditches, is characterized by moderately to heavily encrusted axes, solitary spine-cells and conjoined or sejoined gametangia at 2-4 lowest branchlet nodes. Chara sejuncta grows in the reservoir, particularly in clear water. It has 3-corticate cortex, sejoined gametangia and tetrascutate antheridia. Chara corallina var. kyusyensis growing in shallow water is characterized by ecorticate axes without spine-cells, and rudimentary stipulodes and bract-cells. Chara fibrosa var. microstephana, growing at the paddy fields, is characterized by rudimentary spine-cells, stipulodes of two times as numerous as the branchlets and ecorticate branchlets. A key to the Korean taxa of Chara is provided.