The purpose of this study was to suggest ways to improve adult learning effect. To do this, this study suggested a method to apply breathing meditation considering the characteristics of learners and learning environment in the adult learning field. Study 1 was conducted on 33 adult learners for understanding the effects of breathing meditation on learning. The results confirmed that breathing meditation increases adult learner’s objective concentration. Study 2 was conducted on 137 adult learners. It was confirmed that repeated training of breathing meditation on adult learners improved their attention concentration. The results of this study were as follows. First, breathing meditation improved the concentration ability of adult learners objectively. From these results, we can find out what mechanism breathing meditation can improve attention. Second, the long-term training of breathing meditation improved the attention and class-concentration of adult learners. This long-term training was conducted during the real class of adult learners. Therefore, the generalizability of this study’s results are secured. Third, the effect of breathing meditation was also effective in short term training. Since this training did not require additional learning time or training, it could be used as a simple way to improve the concentration and learning effect of adult learners who were in the job and study simultaneously.This study confirmed the effect of breathing meditation. In the future, if additional research on the new adult learning variables is conducted, it is expected that various learning improvement methods will be developed to help the growing adult learning field.