Aiwo (rarely Aiue, in earlier times Yangor) is a district and constituency in the country Nauru, located in the west of the island. It covers an area of 1.1 km² and a population of 1300. Sometimes, it is called the unofficial capital city of Nauru, although Yaren is mainly titled as Nauru's capital city.

In Aiwo is the main industry located. In this district is:

• the Aiue Boulevard
• the New Boat Port
• the Chinatown of the island
• a youth hostel (the only hotel is in Meneng)
• the power house
• the Nauru Local Government Council chambers and offices
• the NPC processing facilities and cantilever

It returns 2 members to the Nauruan Parliament in Yaren.