Explaining the meaning of felicity and determining its limits is a difficult task. On the other hand, it is an essential concept as it gives sense to life in today's world. In this article, using the descriptive-analytic method, we intend to infer Imam Ali's opinion on this concept based on the teachings of Nahj al-Balaghah. We showed that, according to Imam Ali (AS), the desire felicity only covers the tangible aspect of human existence and does not consider worldly achievements, which is irrational and reprehensible. Moral felicity considers a person's presence (his perceptible and reasonable characteristics), his ultimate goal, and has a rational and praiseworthy nature. Then we stated that according to Imam Ali (AS), the latter felicity is the introduction and foundation of absolute felicity. In this way, we can identify and introduce three meanings of felicity based on Imam Ali's opinion.