Pitchers are the soul and core of a baseball team, and they often play a key role in a baseball game. Pitching speed is very important to success in pitching. There are some factors influenced pitching speed, such as wind speed, muscle strength, psychological, umpire bias in judgment .(Parsons, Sulaeman, Yatesm, Hamermesh, 2011), weather, and so on. From a performance perspective, pitching speed (Matsuo et al., 2001; Werner et al., 2008) has traditionally been accepted as a criterion to assess a pitcher. And it is important that the pitchers generate the velocity from the same release point.( Gray, R. 2002; Perkin, D.,2014; Sandoval, J.,2011) .Much of research has focused on the biomechanics of the skill on pitching performance (Fortenbaugh, Fleisig and Andrews, 2009). Therefore, pitching speed was associated with physical conditioning. And it was very important to select specific and effective training methods increasing pitching speed. The purpose of this special issue is to determine the key physical conditions needed for a pitcher by studying the relationship between pitching speed (PS) and a set of selected physical conditioning variables which, in return, should help coaches design more effective training programs to improve pitchers’ physical conditioning. The results and information derived from this study may be helpful for coaches, physical therapists, and athletic trainers with direct interaction with baseball players.