The present invention relates to a one piece cotton free disposable electronic cigarette, comprising: a mouthpiece, an oil cup, a filter assembly, a heating unit and a power supply arranged in turn, and the power supply being electrically connected with the heating unit. The power supply, a controller unit and a vaporizer device all are directly integrated into the one piece cotton free disposable electronic cigarette of the present invention, therefore the electronic cigarette of the present invention is disposable, which is environment-friendly and hygienic. In addition, oil is directly stored in the oil cup of the one piece cotton free disposable electronic cigarette instead of being stored by cotton, in this way, burning taste can be avoided during inhalation and thereby improving the taste.