Lagos Island is the principal island of the city of Lagos in Nigeria.

Lying in Lagos Lagoon , a large protected natural harbour on the west coast of Africa, the island was home to the original Yoruba fishing village of Eko, which grew into the modern city of Lagos. The city has now spread out to cover the neighbouring islands as well as the adjoining mainland.

Lagos Island is connected to the mainland by three large bridges which cross Lagos Lagoon to the district of Ebute Meta . It is also linked to the neighbouring island of Ikoyi and to Victoria Island. The Lagos harbour district of Apapa faces the western side of the island. Forming the main commercial district of Lagos, Lagos Island plays host to the main government buildings, shops and offices. The Catholic and Anglican Cathedrals as well as the Central Mosque are located here.

The poorer eastern side of the island contains the main markets and the poorer housing. The island is extremely crowded and congested and attempts have been made to build new roads out over the lagoon in order to improve traffic flows.