| Navicula amphiceropsis Lange-Bert. & Rumrich, 2000 |
| Navicula anceps (Ehrenb.) Mann, 1907 |
| Navicula angusta Grunow, 1860 |
| Navicula angustata W. Sm., 1853 |
| Navicula antillarum (Cleve & Grunow) Mann, 1907 |
| Navicula antonii Lange-Bert., 2000 |
| Navicula apiculata Bréb., 1854 |
| Navicula aquaedurae Lange-Bert., 1993 |
| Navicula arcus Ehrenb., 1836 |
| Navicula arenaria Donkin, 1861 |
| Navicula arvensis Hust., 1937 |
| Navicula auriculata Hust., 1944 |
| Navicula aurora Sovereign, 1958 |
| Navicula bacillum Ehrenb., 1839 |
| Navicula baileyana Grunow ex A.W.F. Schmidt, 1874 |
| Navicula bicephala Hust., 1952 |
| Navicula bifissa A. Schmidt, 1897 |
| Navicula bigemmata A. Mann, 1925 |
| Navicula bilobata Leud.-Fortm., 1879 |
| Navicula binodulosa M. Sullivan & Reimer, 1975 |