| Stenostachys Turcz., 1862 |
| Stenotaphrum Trin., 1820 |
| Stenotaphrum americanum Schrank, 1822 |
| Stenotaphrum glabrum Trin., 1820 |
| Stenotaphrum glabrum var. americanum (Schrank) Döll, 1877 |
| Stenotaphrum glabrum var. glabrum Trin., 1820 |
| Stenotaphrum glabrum var. multiflorum Döll, 1877 |
| Stenotaphrum sarmentosum Nees, 1829 |
| Stenotaphrum secundatum (Walter) Kuntze, 1891 |
| Stephanostipa (Speg.) M.K. Elias, 1942 |
| Stephostachys Zuloaga & Morrone, 2010 |
| Stephostachys mertensii (Roth) Zuloaga & Morrone, 2010 |
| Stiburus Stapf, 1900 |
| Stilpnophleum Nevski, 1936 |
| Stipa L., 1753 |
| Stipa (Dasystipa) Speg., 1901 |
| Stipa (Jarava) (Ruiz & Pav.) Trin. & Rupr., 1842 |
| Stipa (Lasiostipa) Speg., 1925 |
| Stipa (Leptostipa) Speg., 1925 |
| Stipa (Microstipa) Speg., 1901 |