The members of the Chlorodendrophyceae are unicellular flagellates, but some species form a dendroid colony in which the cells are connected by stalk (remainder of mother cell theca). Most species inhabit in marine, but freshwater species sometimes forming bloom are also known.

The body of the cell is covered by a thin "theca", which is derived from Golgi body. The "theca" consists of many small scales (homologous to tose of other "prasinophyceans") fused together. Cells are usually laterally compressed, but the cell architecture is basically radially symmetrical. Four homodynamic equal flagella emerge from anterior pit of the cell. The flagella are covered by hair scales and two layers of small scales. The chlorodendrophycean algae possess a single chloroplast. In the chloroplast, a conspicuous large eyespot and the pyrenoid invaginated by cytoplasmic tubes are usually present. Cytokinesis is mediated by the phycoplast.