The capital of Hawaii is Honolulu.

An excerpt from the article 16 facts about Hawaii

The city is located on the island of Oʻahu and is inhabited by approximately 345.000 people. Honolulu has numerous museums, concert halls, an oceanarium, and a zoo. It is also a large educational center, with as many as 8 universities and 2 colleges. There is also an airport in Honolulu - Daniel K. Inouye International Airport.