The purpose of this research was to find out the performance of the players from youth teams in Japanese Professional Football League (J-League) clubs. Firstly, to measure the performance of the players from youth teams, we researched the J-League' s official website referring to the players' participation records. Secondly, we used the Youth Development Index (YDI) and classified the players from youth teams into three groups (starters, substitutes, others) . In this research, we used YDI as the number of the players from youth teams who are starters or substitutes in each club. As a result, it was found that YDI of the entire J-League clubs rose between the 2002 season and the 2010 season. The average YDI of J-League clubs increased from 1.22 (2002 season) to 2.52 (2010 season) . It can be said that youth development achievement has gone up in the entire J-League. On the other hand, it was found that "the others" (the players who were not in YDI) who scarcely participate in the games in top teams increased more than YDI. It was shown that the number of "the others" increased from 1.33 (2002 season) to 4.11 (2010 season) . Thus it can be said that this is a problem to be solved in the entire J-League.