This research aims to study the importance of serving efficiency in tennis. It is applied to nineteen labeled players, who have participated in the following international championships: 1-Masters-tennis tournament 2011 London; 2-Hamburg Tennis tournament; -3-china open tennis tournament2013 4-shanghai rolex masters 2013. Results of these tournaments have been analyzed and yielded the following results: the accuracy and efficiency of surving play a critical role in determining the result of the game, especially when levels of the two players are very close. Absence of focus and loss of accuracy in serving leads to increase in the number of double fault. That in turn leads to losing too many rounds in games and it also leads contender to win faultless rounds without any effort. When the player has too many aces in games, he will always be in attacking position. This is a conformation, which proves that the powerful efficiency of serving is confusing the contender and making him occupied with a defence position all the time.