Purpose: To investigate how world top tennis players' first and second serve speed and placement contributes to their on-court performance. The placement was divided into wide serves (Wide), serves to the receiver's body (Body), and those to the center line (T). Methods: Data collection from the third round to the men's single final of the 2004 US Open official site was processed to get the serve-related figures and then analyzed by two-way ANOVA mixed design. Results: For the serve placement and average speed there was no significant difference between the winner and loser. However, the winner had high percentage of the first to the placement of Wide and Body; and the second serve to the T from the deuce court. While at the advantage court, the first serve was tending to the Wide. For all the players the first serve placement from the deuce court was Wide＞T＞Body and T & Wide＞Body from the advantage court (p＜.05), while the second serve was mostly aimed toward the Body. The average first serve speed from the deuce court were T＞Body＞Wide, and Wide＞Body & T for the average second serve speed (p＜.05). From the advantage court, it was T＞Body＞Wide for the average first serve speed and Wide＞Body & T (p＜.05). All players had significant lower winning percentage on the first serve that was directed right toward the Body rather than the Wide or T. Conclusion: For all top men's tennis players, winner or loser of a given game, the serve placement and the average serve speed were quite the same, which indicated they adopted an identical serve strategy and all possess the capability to carry it out. However, significant difference could be found in the point winning ability when serve from the deuce court, the first serve toward the Wide, Body and the second serve toward T, and when serving from the advantage court, the first serve toward the Wide. That might be the key to a player's performance on the court.