Yes, you can use Disney Gift Cards on a Disney Cruise, but they work slightly differently than at the theme parks. Since Disney Cruise Line operates on a "cashless" system, you cannot use a physical gift card to pay for individual drinks or souvenirs at the shops. Instead, you must visit the Guest Services desk on Deck 3 to "load" the gift card balance onto your onboard stateroom account. Once the balance is applied, it will be used to offset any charges you make with your Key to the World card. It is highly recommended to keep your physical gift cards even after they are "spent," because if you have a remaining credit at the end of the cruise, it will be refunded back to the original card. You can also use Disney Gift Cards before you set sail to pay for your cruise fare, excursions, or spa treatments via the Disney Cruise Line website or by calling their reservation line.