Social networks have a very important role in tourism business. The goal of this paper is to understand the history of development and the notion of social network, its potential that can be implemented for business purposes, for both large and small entrepreneurs and especially those in tourism. Through more detailed analysis and definition of social networking tools, explain their application in the branches of tourism business, precisely in the most important sectors that occupy the highest percentage of the market and generetae the largest profits, namely hotels, restaurants, airlines, small travel agencies and turoperators. Statistical data credibly depicts the social network use in tourism business, together with the advantages and disadvantages deriving from the use of social networks and a critical review based on the effort to determine whether the social network is a modern support to tourism business? Based on the application of social networks in the case analysis of Tuscany, the region in the Italy, explore the efficiency and contribution of social networks to the regions tourism prosperity. Finally, in the conclusion of the paper encompass the whole concept of work, and with all the analyzed data and information so far, to sum up the essence of social network and their necessity in the application in the tourism business process.