1. Labridae G. Cuvier 1816
2. Laelapidae Berlese 1892
3. Laganidae Desor 1858
4. Lamiaceae Martynov 1820
5. Lampeidae Krumbach 1925
6. Lampropidae Sars 1878
7. Lampyridae Latreille 1817
8. Laniidae Rafinesque 1815
9. Laodiceidae Agassiz 1862
10. Laophontidae T. Scott 1904
11. Laqueidae Thomson 1927
12. Lasaeidae Gray 1842
13. Laternulidae Hedley 1918 (1840)
14. Latidae D.S. Jordan 1888
15. Latreilliidae Stimpson 1858
16. Lauraceae de Jussieu 1789
17. Lecanidae Remane 1933
18. Leiodidae Fleming 1821
19. Leiognathidae T.N. Gill 1893
20. Leiothrichidae Swainson 1831
21. Lentibulariaceae Richard 1808
22. Lepisosteidae Cuvier 1825
23. Leporidae Fischer de Waldheim 1817
24. Leptoceridae Leach in Brewster 1815
25. Leptocheliidae Lang 1973
26. Leptochitonidae Dall 1889
27. Lernaeidae Cobbold 1879
28. Lernanthropidae Kabata 1979
29. Lessoniaceae Setchell & Gardner 1925
30. Lestidae Calvert 1901
31. Lethrinidae Bonaparte 1831
32. Leucettidae de Laubenfels 1936
33. Leuconidae Sars 1878
34. Leucosiidae Samouelle 1891
35. Leucotheidae Krumbach 1925
36. Libellulidae Rambur 1842
37. Lichomolgidae Kossmann 1877
38. Liliaceae de Jussieu 1789
39. Limnephilidae Kolenati 1848
40. Limulidae Leach 1819
41. Lineidae McIntosh 1873-1874
42. Lingulidae Menke 1828
43. Linognathidae Webb 1946
44. Linuchidae Haeckel 1879
45. Liopteridae Ashmead 1895
46. Liparidae T.N. Gill 1861
47. Lithodidae Samouelle 1819
48. Lithotryidae Gruvel 1905
49. Litiopidae Gray 1847
50. Littorinidae Children 1834
51. Lituolidae de Blainville 1827
52. Lobatolampeidae Horita 2000
53. Lobophylliidae Dai & Horng 2009
54. Lomentariaceae J. Agardh 1876
55. Lophiidae Rafinesque 1810
56. Lophogastridae G.O. Sars 1870
57. Lophotidae Bonaparte 1845
58. Loricariidae Rafinesque 1815
59. Loricidae Iredale & Hull 1923
60. Lottiidae Gray 1840
61. Lovenellidae Russell 1953
62. Lucanidae Macleay 1819
63. Lucinidae J. Fleming 1828
64. Luidiidae Sladen 1889
65. Lumbricidae Rafinesque & Schmaltz 1815
66. Lumbrineridae Schmarda 1861
67. Lutjanidae T.N. Gill 1861
68. Lycosidae Sundevall 1833
69. Lymnaeidae Rafinesque 1815
70. Lyroctenidae Komai 1942
71. Lythraceae J. St.-Hilaire 1805