| Navicula minuscula Grunow, 1880 |
| Navicula minutissima (Kütz.) Grunow, 1860 |
| Navicula molaris Grunow, 1863 |
| Navicula molestiformis Hust., 1949 |
| Navicula monilifera Cleve, 1895 |
| Navicula monoculata Hust., 1945 |
| Navicula moralesii Metzeltin & Lange-Bert., 2007 |
| Navicula muscaeformis Grunow, 1875 |
| Navicula mutica Kütz., 1844 |
| Navicula mutica f. goeppertiana Bleisch, 1861 |
| Navicula mutica var. cohnii (Hilse) Grunow, 1880 |
| Navicula namibica Lange-Bert. & Rumrich, 1993 |
| Navicula neglecta Kütz., 1844 |
| Navicula neoventricosa Hust., 1966 |
| Navicula nivalis Ehrenb., 1853 |
| Navicula nolens Simonsen, 1959 |
| Navicula notha Wallace, 1960 |
| Navicula oblonga (Kütz.) Kütz., 1844 |
| Navicula oblongella Nägeli ex Kütz., 1849 |
| Navicula obsoleta Hust., 1942 |