| Peridinium murrayi Kof., 1907 |
| Peridinium murrayi var. occidentalis Pavill., 1930 |
| Peridinium murrayi var. orientalis Matzen., 1933 |
| Peridinium oblongum (Auriv.) Cleve, 1900 |
| Peridinium oceanicum Vanhöffen, 1897 |
| Peridinium okamurai T.H. Abé, 1927 |
| Peridinium orbiculare Paulsen, 1907 |
| Peridinium ovatum (Pouchet) Schütt, 1895 |
| Peridinium oviforme P.A. Dang., 1927 |
| Peridinium pacificum Kof. & Michener, 1911 |
| Peridinium palatinum Lauterbom, 1896 |
| Peridinium pallidum Ostenf., 1899 |
| Peridinium parallelum Brock, 1906 |
| Peridinium paulsenii Mangin, 1911 |
| Peridinium penardii (Lemmerm.) Lemmerm., 1910 |
| Peridinium pentagonum Gran, 1902 |
| Peridinium polonicum Woloszynska, 1916 |
| Peridinium polyedricum Pouchet, 1883 |
| Peridinium pseudointermedium Couté & A. Iltis, 1984 |
| Peridinium pulvisculus Ehrenb., 1830 |