| Ocimum basilicum L. | MAKS1393 |
| Oenanthe javanica DC. | MAKS2054 |
| Ophiopogon ? | MAKS2163 |
| Ophiopogon jaburan (Kunth) Lodd. | MAKS2155, MAKS2156, MAKS2161 |
| Ophiopogon japonicus (L. fil.) Ker-Gawl. | MAKS0807, MAKS2162 |
| Oplismenus undulatifolius (Ard.) Roemer et Schultes | MAKS2468, MAKS2470, MAKS2464 |
| Orchis graminifolia (Reichb. fil.) Tang et Wang | MAKS0750 |
| Orostachys malacophyllus (Pallas) Fisch. | MAKS2106 |
| Oryza sativa L. | MAKS2562, MAKS2560, MAKS2561, MAKS2558, MAKS2559 |
| Osmanthus fragrans Lour. var. thunbergii Makino | MAKS1108 |
| Osmanthus heterophyllus (G. Don) P. S. Green | MAKS1109, MAKS1110, MAKS1111, MAKS1256 |
| Ottelia japonica Miq. | MAKS0742, MAKS2120, MAKS2121 |
| Oxalis corniculata L. | MAKS1229 |
| Oxalis corniculata L. f. erecta Makino | MAKS1232 |
