This is a question that is up for debate and quite possibly does not have one definitive answer at all. Every country has beautiful girls that are attractive in their own right and in their own unique ways. Determining the answer to this question would be purely based on opinion and would vary depending on who you are asking.
With that said by popular opinion there are a few countrues that are looked at as having more beautful women. Some of the top ones are Columbia, Denmark, South Korea, The Ukraine, and Brazil. Some may find that these top 5 places are a cut above the rest.