NadiGisele, it would be helpful if you mentioned where you are from.
Having said that, most nationalities don't need visas, but have to buy a tourist card which costs US$10 - you can get it in advance from your nearest Dominican consulate, or on arrival at the airport. Have the correct sum in US dollars ready. Some travel companies/airlines may include the tourist card in the holiday package so check with your travel agent.
Buen viaje!
Chiri
