| Cyperus gracilis Link, 1820 |
| Cyperus granadinus Liebm., 1850 |
| Cyperus guadalajaranus M.E. Jones, 1933 |
| Cyperus guatemalensis Gand., 1919 |
| Cyperus haenkei J. Presl & C. Presl, 1830 |
| Cyperus hartii Boeckeler, 1888 |
| Cyperus haspan L., 1753 |
| Cyperus haspan f. coarctatus (Nees) Osten, 1931 |
| Cyperus haspan subsp. juncoides (Lam.) Kük., 1926 |
| Cyperus haspan var. americanus Boeckeler, 1868 |
| Cyperus haspan var. coarctatus Nees, 1842 |
| Cyperus haspan var. riparius (Schrad. ex Nees) Kük., 1936 |
| Cyperus hayesii (C.B. Clarke) Standl., 1925 |
| Cyperus heermannii Buckley, 1862 |
| Cyperus helodes Nees, 1842 |
| Cyperus helvus Liebm., 1850 |
| Cyperus hemioccidentalis Goetgh., 2014 |
| Cyperus hermaphroditus (Jacq.) Standl., 1916 |
| Cyperus hermaphroditus var. longiradiatus (Liebm.) Kük., 1936 |
| Cyperus herndoniae G.C. Tucker, 1982 |