| Homalocenchrus monandrus (Sw.) Kuntze, 1891 |
| Homalocenchrus oryzoides (L.) Haller, 1768 |
| Homoeatherum Nees ex Lindl., 1836 |
| Homoiachne Pilg., 1949 |
| Homolepis Chase, 1911 |
| Homolepis aturensis (Kunth) Chase, 1911 |
| Homolepis glutinosa (Sw.) Zuloaga & Soderstr., 1985 |
| Homolepis isocalycia (G. Mey.) Chase, 1911 |
| Homopogon Stapf, 1908 |
| Hopia Zuloaga & Morrone, 2007 |
| Hopia obtusa (Kunth) Zuloaga & Morrone, 2007 |
| Hoplismenus Hassk., 1844 |
| Hordeiformae J.G. Sm., 1899 |
| Hordeinae Dumort., 1829 |
| Hordeum L., 1753 |
| Hordeum (Zeocriton) (Wolf) Hack., 1887 |
| Hordeum adscendens Kunth, 1816 |
| Hordeum arizonicum Covas, 1949 |
| Hordeum avenaceum Wiggins ex P. Beauv., 1812 |
| Hordeum berteroanum É. Desv., 1854 |