目的：本文主要比較臺灣公開女生一級排球選手與一般女生組排球選手在面對肩上漂浮發球的接發球重心位移速度及重心高度分析及探討。針對競技運動特殊性來探討排球選手在接發球過程中是否因為適當的接球重心而增加接球成功率。方法：使用Fastec Inline 攝影機兩部，擷取頻率為每秒250Hz 進行同步拍攝，並蒐集兩種等級受試者之接發球動作人體運動學參數，以Tracker及Kwon3D動作分析軟體進行運動學參數分析，在運動學參數比較方面，將得到參數資SPSS 14.0 版統計軟體進行統計分析，以獨立樣本t-test檢驗兩種等級在接發球時觸球期重心合速度及重心高度是否有差異，統計水準定為α＝.05。結果：公開女生一級與一般女生組在接發球時重心合速度未達現著差異，而在接球時重心高度，公開女生一級選手重心低於一般女生組選手達顯著差異(p<.05)。結論：1、公開女生一級選手接球重心高度低於一般女生組選手，顯示接球重心高度會影響接球成功率及到位率，最佳接球重心高度應以0.521m~0.624m 之間為最佳。2、公開女生一級選手重心起伏較一般女生組小，由重心位移軌跡圖表顯示，公開女生一級選手從準備期就保持低重心的準備姿勢，待球發出後立即位移至接球位置，而一般女生組選手重心起伏過大，容易造成判斷上的失誤，增加直接接發失誤的機率。

Objective: The purpose of this study was to compare the advanced women’s volleyball players to the average players when confronting the floating serving, which analyzed their speed and their altitude of shifting center of gravity. By focusing on the particularity of athletics, we were able to tell whether the volleyball players employed the appropriate center of gravity to receive the ball. Therefore, we were able to increase the success rate of receiving the ball. Method: Shoot by using two Fastec Inline cameras with 250Hz and collect the parameters of two different levels of player. Analyzing the kinematic parameters by using Tracker and Kwon3D, we would get the details of the parameters. Therefore, analyze the parameters by the software SPSS 14.0. The standard statistics a=.05. Use the independent t-test to examine whether there were significant level in the speed and the altitude of shifting center of gravity when the players serving the balls. Result: There was no significant level of the speed of shifting center of gravity between the advanced players and the average players. The altitude of the shifting center of gravity of the advanced players was lower than the average players. The difference was p<.05. Conclusion: 1.The accuracy of receiving the ball of the advanced players was higher than that of the average player. Besides, their center of gravity when receiving the ball was lower than the average players. Therefore, the altitude of center of gravity had much influence on the success rate of receiving the ball and on the correct place reached by the ball. The best altitude of the shifting center of gravity was between 0.521m〜0.624m. 2. The change of shifting center of gravity of the advanced players was smaller than that of the average players. Judging from the locus of shifting center of gravity, it was clear that the advanced players already lowered their center of gravity in preparation to receive the ball. The average players’ change of shifting center of gravity was larger, causing the error in judgment and increasing the possibility.