Though the cuban peso is the official currency in Cuba, the convertible peso (CUC) is the one that the tourist must use. It is equal to one american dollar.

If tourists want to use american dollars they have to pay, in change, a charge of 10%. The cuban peso is only use in Cuba, and its exportation or importation is prohibited.

In some tourist places like Holguín, Varadero and Jardines del Rey it is possible to use Euros. 

You can exchange your money for convertible pesos at the airports, hotels, banks and exchenge offices (CADECA S.A.)