| Arpa | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Armenia, Azerbaijan |
| Length Km: | 128 |
| Mouth: | Aras |
| Mouth Coordinates: | 39.4686°N 44.9469°W |
| Basin Size Km2: | 2630 |
The Arpa (hy|Արփա; az|Arpaçay) is a river that flows through Armenia and Azerbaijan's Nakhchivan exclave. Originating in Armenia's Vayots Dzor province (marz), it is a left tributary of the Aras. It is 128km (80miles) long, and has a drainage basin of 2630km2.[1] It runs through many cities and towns, including Jermuk, Vayk, Yeghegnadzor, Areni, Oğlanqala, Siyaqut and Qışlaqabbas.