| Heleophylax americanus (Pers.) Schinz & Thell., 1909 |
| Hemicarpha Nees & Arn., 1834 |
| Hemicarpha caespitula (Liebm.) Palla, 1908 |
| Hemicarpha micrantha (Vahl) Pax, 1888 |
| Hemicarpha micrantha var. minor (Schrad.) Friedl., 1941 |
| Hemicarpha subsquarrosa (Muhl.) Nees, 1842 |
| Hemicarpha subsquarrosa var. minor (Schrad.) Nees, 1842 |
| Holoschoenus Link, 1827 |
| Holoschoenus mexicanus Palla, 1913 |
| Hypaelyptum Vahl, 1806 |
| Hypolytreae Nees ex Wight & Arn., 1834 |
| Hypolytrum Rich. ex Pers., 1805 |
| Hypolytrum capillare Schrad. ex Nees, 1842 |
| Hypolytrum longifolium (Rich.) Nees, 1834 |
| Hypolytrum longifolium subsp. nicaraguense (Liebm.) T. Koyama, 1967 |
| Hypolytrum nicaraguense Liebm., 1850 |
| Hypoporum Nees, 1834 |
| Hypoporum hirtellum (Sw.) Nees, 1834 |
| Hypoporum humile Nees, 1834 |
| Hypoporum interruptum Torr., 1836 |