| Cassia durangensis var. durangensis Rose, 1906 |
| Cassia durangensis var. iselyi H.S. Irwin & Barneby, 1975 |
| Cassia ekmaniana Urb., 1928 |
| Cassia elliptica Kunth, 1824 |
| Cassia emarginata L., 1753 |
| Cassia emarginata var. subunijuga B.L. Rob. & Bartlett, 1907 |
| Cassia enneandra Brandegee, 1915 |
| Cassia excelsa Kunth, 1824 |
| Cassia exigua Roxb., 1814 |
| Cassia fabaginifolia Kunth, 1824 |
| Cassia fagonioides Vogel, 1837 |
| Cassia fasciculata Michx., 1803 |
| Cassia fistula L., 1753 |
| Cassia fistuloides Collad., 1816 |
| Cassia flavicoma Kunth, 1824 |
| Cassia flavicoma var. paraguariensis Chodat & Hassl., 1904 |
| Cassia flexuosa L., 1753 |
| Cassia floribunda Cav., 1802 |
| Cassia florida Vahl, 1794 |
| Cassia foetida Sessé & Moc., 1894 |