| Saccharum villosum Steud., 1854 |
| Saccharum violaceum Tussac, 1808 |
| Sacciolepis Nash, 1901 |
| Sacciolepis gibba (Elliott) Nash, 1901 |
| Sacciolepis myuros (Lam.) Chase, 1908 |
| Sacciolepis striata (L.) Nash, 1903 |
| Sacciolepis striata f. gibba (Elliott) Fernald, 1942 |
| Salmasia Bubani, 1901 |
| Salmasia flexuosa (L.) Bubani, 1901 |
| Salmasia vulgaris Bubani, 1901 |
| Sanguinaria Bubani, 1901 |
| Sanguinaria ciliaris (Retz.) Bubani, 1901 |
| Sanguinella Gleichen, 1764 |
| Santia Savi, 1799 |
| Santia monspeliensis (L.) Parl., 1845 |
| Sarga Ewart & White, 1911 |
| Sarga trichoclada (Rupr. ex Hack.) Spangler, 2003 |
| Saugetia Hitchc. & Chase, 1917 |
| Savastana Schrank, 1789 |
| Schaffnera Benth., 1882 |