Sports gambling has been an attractive controversy for a long time. Fantasy sports, similar to most sports lotteries and gambling, allows customers to put bets of their choices of players and win certain rewards according to the real game data in each famous Sports League such as NFL, MLB, NBA, etc. Although Fantasy sports has always been at the forefront of legal issue discussions, it has become a popular activity of Americans. Even media are invading this grey industry to support data analysis and news for citizens’ pleasure. Despite the negative influence of sports gambling, there are several bright aspects of Fantasy Sports. It is a good activity between friends and families instead of letting vulnerable people such as kids be influenced by illegal sports gambling. In addition, in place of letting illegal sports gambling companies overseas, which will benefit the U.S. economy, to grab market share, it is better to create a legal and popular sports gambling application through PC or other mobile devices to draw public interests. This study attempts to design a Fantasy Sports application for those traditional prosperous gambling industries such as Casinos in Las Vegas or Casinos in Macau to support Fantasy Sports. A software development process and development tools are introduced in this paper and the prototype of the application are created as well in this proposal.