This paper deals with karyological studies on four species of the genus Entodon from China. The metaphase and heteropycnotic chromosomes in mitotic cells of gametophytes were observed. All the four species showed the same chromosome number of n = 11.Their karyotypes were formulated as K (n) = 11 = 2V (H) +2J + 6 ( 4v + 2i) + m (h) in E.obtusatus , E. compressus , E. okamurae and K ( n ) = ll = 2V ( H ) + l V + 2J + 5 ( 3v +2i ) +m(h) in E. giraldii, respectively.