Happiness may be in the state of focus, joy, and peace at present, or may be also a general term for a happy life. Recently, there’re two popular curricula of life education in America; One is the course of happiness in The Harvard University, and the other is mindfulness based stress reduction course by Dr. Kabakin. This two courses remind us that in every busy life we forget, and happiness needs learning, joy needs learning, focusing on the present happy life also needs learning. Currently, the clinical and psychology field in America as well as Europe have regarded "Mindfulness Therapy" originated from Buddhism as an important treatment technique, aiming to ease mental and physical stress as well as to promote social welfare. This article tries to lay the foundation on mindfulness of early Buddhist scriptures, taking "Mindfulness Therapy" as the theme of happiness studying and mindfulness diary as happiness index, expecting to investigate mindfulness of the road to happiness.