| Piper obtusifolium L., 1753 |
| Piper ocosingosense Callejas, 2020 |
| Piper oradendron Trel. & Standl., 1952 |
| Piper orizabanum C. DC., 1898 |
| Piper otophorum C. DC., 1891 |
| Piper ottoniifolium C. DC., 1866 |
| Piper pachoanum C. DC., 1920 |
| Piper palenquense Callejas, 2020 |
| Piper palmeri C. DC., 1895 |
| Piper pansamalanum C. DC., 1920 |
| Piper papantlense C. DC., 1869 |
| Piper patulum M. Martens & Galeotti, 1843 |
| Piper patzulinum Trel. & Standl., 1952 |
| Piper pellucidum L., 1753 |
| Piper peltatum L., 1753 |
| Piper pennellii Trel. & Yunck., 1950 |
| Piper peracuminatum C. DC., 1920 |
| Piper pergamentifolium Trel. & Standl., 1952 |
| Piper perhispidum C. DC., 1920 |
| Piper phytolaccifolium Opiz, 1828 |