Brain Respiration (BR)-training is a unique form of breathing exercise that develops potential ability by facilitating brain function. It is recognized as an effective method of improving the scholastic aptitude and emotional stability of children. The present study was designed to investigate the characteristics of the EEG during this training. Spectral analysis was used to examine the relative power in the EEG of 12 children while they practiced BR-training, and these were compared to those of 12 matched controls. BR-trainees showed a lower theta rhythm than the controls before the training session began and lower beta2 power before, during and after the session. In contrast, the BR subjects showed greater relative alpha1 power than the controls in the left frontal region during BR-training, which persisted throughout the BR-training schedule. There is evidence that decreased theta and beta waves may be correlated with emotional maturation, whilst increased alpha waves are associated with educational achievement. These findings enhance our understanding of the neurophysiological basis of the effects of BR-training upon emotion and maturation.