| Navicula obtusa (Lagerst.) Hust., 1909 |
| Navicula orbiculata Patrick, 1959 |
| Navicula ostrogothica Cleve-Euler, 1953 |
| Navicula oxyptera Kütz., 1844 |
| Navicula palpebralis Bréb., 1853 |
| Navicula palpebralis var. minor (W. Greg.) Grunow, 1867 |
| Navicula parca A. Schmidt, 1875 |
| Navicula parva (Ehrenb.) Ralfs, 1861 |
| Navicula patrickae Hust., 1955 |
| Navicula pavillardii Hust., 1939 |
| Navicula pelagi A. Schmidt, 1875 |
| Navicula pelagica Cleve, 1896 |
| Navicula pelliculosa Bréb. ex Kütz., 1863 |
| Navicula pennata A. Schmidt, 1876 |
| Navicula peregrina (Ehrenb.) Kütz., 1844 |
| Navicula peregrina var. acuta (Ant. Mayer) Frenguelli, 1942 |
| Navicula permagna (Bailey) A.M. Edwards, 1859 |
| Navicula perminuta Grunow, 1880 |
| Navicula perrostrata Hust., 1936 |
| Navicula petersenii Hust., 1937 |