| Attalus III Philometor Euergetes | |
|---|---|
 Attalus III (or II), 150/152 BC from Antikensammlung in Berlin. | |
| King of Pergamon | |
| Reign | 138–133 BC |
| Predecessor | Attalus II |
| Successor | Eumenes III |
| Born | c. 170 BC |
| Died | 133 BC |
| Greek | Άτταλος Γ΄ Φιλομήτωρ Ευεργέτης |
| House | Attalid dynasty |
| Father | Eumenes II |
| Mother | Stratonice of Cappadocia |
| Religion | Greek Polytheism |
Attalus III (Greek: Ἄτταλος Γ΄) Philometor Euergetes (c. 170 BC – 133 BC) was the last Attalid king of Pergamon, ruling from 138 BC to 133 BC.