Koliellaceae is a family of green algae in the order Prasiolales.

[1] Koliellaceae was circumscribed by František Hindák in 1996 to include various green algae that reproduce mainly by simple cell division.

[2] The taxonomy of this family is problematic because molecular phylogenetics have shown the type genus Koliella is polyphyletic.

The type species of Koliella, K. spiculiformis, forms a clade that is closely related to Chlorella; meanwhile, most other species of Koliella and Raphidonema are part of a clade including Prasiola and Stichococcus.

[3] Since Hindák's circumscription, a number of genera have been added to the family Koliellaceae based on their placement in their placement in the latter clade, that differ from its original morphological definition.