The liner is being towed to San Diego by tugboats after a fire that disabled its engines, and should be there by midday Friday.
The Ministry of Foreign Affairs says New Zealand's consulate-general in Los Angeles has contacted the ship's owners to make sure none of the New Zealanders has any medical conditions and has been assured they are all well.
The ministry says communication with the ship is limited, with only outgoing phone lines available for use by passengers.
The Carnival Splendor, which is carrying 4500 people, was on a seven-day cruise of the Mexican Riviera.
The ship has had no air-conditioning or hot water, and passengers have been eating canned crab meat and Spam dropped by military helicopters.
The company says passengers will get a full refund, their travel expenses will be paid and they will receive another cruise equal to the cost of the trip.