The purpose of this study is to explore the happy life experienced by adult learners in the daily life of graduate school. It is to explore the perception of happiness that adult learners experience in their daily life in graduate school and to explore the impact of happiness experiences on their lives. For this purpose, two research questions were set. First, what is the perception of happiness experienced by adult learners in the daily life of graduate school. Second, what is the impact of adult learners' happiness experiences on their lives in the daily life of graduate school. For these research questions and research purposes, in-depth interviews were conducted with eight adult learners belonging to C University's general graduate school. Data analysis was conducted using Colaizzi's phenomenological content analysis method, and interpretation was based on Seligman's (2011) theory of happiness. As a result of the study, adult learners experienced a happy life while feeling positive emotions such as pleasure, vitality, immersion, reward, and pride in the process of learning and researching together in graduate school. The impact of these happiness experiences on the lives of adult learners was found to be positive and negative changes in two areas of life. First, in the personal life domain, the experience of academic achievement had a positive effect on psychological and emotional aspects. On the other hand, experiencing an imbalance in life while juggling work, family, and studies had a negative impact on the physical aspect. Second, the positive interpersonal experience of living well with others in the field of social life led to a change in the attitude to study receptively and self-directedly.