Moroni (in Arabic موروني Mūrūnī) is the largest city of the Comoros islands and since 1958 has served as its capital. In Comorian, Moroni translates as "in the heart of the fire", perhaps alluding to the city's proximity to Mount Karthala. The city's estimated population in 2003 was 60,200 residents.

Moroni was founded by Arabic settlers possibly during the 10th century AD as the capital of a sultanate connected commercially to Zanzibar in Tanzania.

The city is located on the western coast of Grande Comore (also known as N'gazidja) island. Moroni is served by the Prince Said Ibrahim International Airport (IATA airport code: HAH). There is also a harbour with regular transport to the African mainland and the other islands in the Comoros archipelago, as well as Madagascar and other Indian ocean islands. Moroni is located at 11°45′S 43°12′E / 11.75°S 43.2°E / -11.75; 43.2Coordinates: 11°45′S 43°12′E / 11.75°S 43.2°E / -11.75; 43.2.

Exports include vanilla, cocoa, and coffee.

Moroni has many excellent beaches. The Ancienne Mosquée du Vendredi (Old Friday Mosque) is a popular tourist spot. The city is featured in the game Where in the World Is Carmen Sandiego?

The Comoros ⁱ/ˈkɒməroʊz/ (Arabic: جزر القمر‎, Ǧuzur al-Qumur/Qamar), officially the Union of the Comoros (Comorian: Udzima wa Komori, French: Union des Comores, Arabic: الاتحاد القمري‎ al-Ittiḥād al-Qumurī/Qamarī) is a sovereign, archipelago island nation in the Indian Ocean, located off the eastern coast of Africa, on the northern end of the Mozambique Channel, between northeastern Mozambique and northwestern Madagascar. Other countries near to the Comoros are Tanzania to the northwest and the Seychelles to the northeast. The capital is Moroni on Grande Comore.

At 1,862 km² (719 sq mi) (excluding Mayotte), the Comoros is the third-smallest African nation by area. The population (excluding Mayotte) is estimated at 798,000. Its name derives from the Arabic word قمر qamar ("moon"). The archipelago is notable for its diverse culture and history, as a nation formed at the crossroads of many civilizations. It is the southernmost member state of the Arab League. Though in the contested island of Mayotte the sole official language is French, the "Union of the Comoros" has three official languages: Comorian, Arabic, and French.