Volvulina is a genus of colonial green algae in the family Volvocaceae.

[1] The colony (coenobium) is broadly ellipsoidal or spherical and consists of a fixed number of cells, usually 16 in mature individuals (rarely 4, 8 or 32).

The cells are located at periphery of the coenobium and separated from each other by being embedded in a swollen sack.

The cell body is lens-shaped or half spherical when mature with two flagella.

Pyrenoids may be present or absent, the stigma large.