"This is an outline of the studies the author conducted on Baseball and Eye. A series of studies revealed the following. 1. The batter need to see the ball for at least four fifths of the entire distance in order to hit it successfully. 2. A significant correlation rate of 0.785 was noted between batting eye and batting average. This study therefore indicates that batting average is related to batting eye. 3. If the speed of the second ball was faster than that of the first ball, it was observed that the greater the difference between the speeds of the two balls, the faster the batter perceived the speed of the second ball to be. If the speed of the second ball was slower than that of the first ball, it was observed that the greater the difference between the speeds of the two balls, the slower the batter perceived the speed of the second ball to be. 4. Baseball balls were marked with a black 5 mm dot. The explanation of these results could be that focusing the sight on the dot makes the batter aim at the dot when striking the ball. This hitting method may be utilized in actual training of baseball players. 5. For all subjects who specialized in baseball, the highest accuracy in ball throwing was observed with the medium-size target, which was followed by the small target, the large target and no target in descending order. This result may be explained by the long distance set for the baseball players between the players and target which made the smallest target too small for the subjects to exercise any control when throwing their ball. "