- Habronematidae Chitwood & Wehr 1932
- Haematoloechidae Odening 1964
- Haemonchidae Skrjabin & Schulz 1937
- Haemulidae T.N. Gill 1885
- Haleciidae Hincks 1868
- Halichondriidae Gray 1867
- Halictidae Thomson 1869
- Halimedaceae Link 1832
- Haliotidae Rafinesque 1815
- Haliplidae Aubé 1836
- Halymeniaceae Kützing 1843
- Hamamelidaceae R. Brown 1818
- Haminoeidae Pilsbry 1895
- Haploniscidae Hansen 1916
- Haplophragmoididae Maync 1952
- Haploporidae Nicoll 1914
- Harpacticidae Dana 1846
- Hauerinidae Schwager 1876
- Hebellidae Fraser 1912
- Helicarionidae Bourguignat 1877
- Helicidae Rafinesque 1815
- Helicinidae Férussac 1822
- Heligmonellidae Skrjabin & Schikhobalova 1952
- Heligmosomatidae Cram 1927
- Heligmosomidae Travassos 1914
- Hemiramphidae T.N. Gill 1859
- Hemiscylliidae Gill 1862
- Hemithirididae Rzhonsnitskaia 1956
- Hemitripteridae T.N. Gill 1872
- Hemiuridae Looss 1899
- Herpestidae Bonaparte 1845
- Hesionidae Grube 1850
- Hesperiidae Latreille 1809
- Heterakidae Railliet & Henry 1914
- Heteralepadidae Nilsson-Cantell 1921
- Heterodontidae J.E. Gray 1851
- Heterophyidae Odhner 1914
- Heteroxynematidae Skrjabin & Shikhobalova 1948
- Hexagrammidae T.N. Gill 1863
- Hexamitidae Kent 1880
- Hiatellidae Gray 1824
- Hildenbrandiaceae Rabenhorst 1868
- Hippoboscidae Samouelle 1819
- Hippolytidae Spence Bate 1888
- Holocentridae J. Richardson 1846
- Holothuriidae Burmeister 1837
- Hominidae Gray 1825
- Hoplichthyidae Kaup 1873
- Hormathiidae Carlgren 1932
- Hyalellidae Bulycheva 1957
- Hyalidae Bulycheva 1957
- Hydrangeaceae Dumortier 1829
- Hydrocenidae Troschel 1857
- Hydrocharitaceae de Jussieu 1789
- Hydrodictyaceae Dumortier 1829
- Hydrometridae Billberg 1820
- Hydrophilidae Latreille 1802
- Hydropsychidae Curtis 1835
- Hylidae Rafinesque 1815
- Hymenolepididae Ariola 1899
- Hynobiidae Cope 1860
- Hypnaceae Schimper 1851
- Hypoptychidae Steindachner 1880
- Hypothalassiidae Karasawa & Schweitzer 2006