Traditionally Epicurus’ philosophy is divided in three areas: Physics, Canonic and Ethics. These areas dialog among themselves and they can’t be understood disconnected one from the others. Thus, this dissertation will be splitted into four parts: the first part will be dedicated to physics, analyzing the Epicurus` challenge of continuing the atomism exalted by Democritus and the democritian economical physics, based on the two primordial elements which allow the total comprehension of the cosmic order, as well as the manner that epicurean sensualism disagreed from those that only had accepted the being and the material; The second one will deal with the Canonic, once after having studied the physiology, it becomes vital to examine the subject of knowledge and its origin, likewise the way that epicureans determined what is knowable and what was the origin of the language; in the third part, will be studied the Ethic in the light of the themes of happiness and pleasure, clarifying what Epicurus considered as pleasure and as a blessed life, such as this philosopher dealt with the use of pleasure, defining how should be the attitude and the action of those men who long for happiness, opposing the hedonistic thesis; in the fourth part, will be advocate a view of epicurism as a therapeutic and prescriptive philosophy, based mainly on the ascetic ideal of the cultivation of oneself for a happy life.