Introduction. The article is devoted to the ethics of transhumanism as a philosophical trend that elevates hedonistic values to the main principle of human existence. The desire to live without pain and without suffering here and now does not require explanation, while exhortations to suffering in earthly life for the sake of an illusory nirvana raise many questions. The difficulty in assessing transhumanist ideas is associated with the rigid determinism of human life by the technosphere. Theoretical analysis. The ideas of the ancient Greeks as the founders of hedonism about achieving happiness largely coincide with the main ideas of the ethics of hedonistic transhumanism. A priori, technology contains a hedonistic essence. The ancient Greeks were guided in achieving happiness by technology as an activity, and representatives of transhumanism understand it as a means of activity. Conclusion. The ideas of transhumanism represent the natural desire of a man to get rid of suffering, thus they continue the ideas of ancient hedonism. The only difference lies in a more advanced technology, the development of which can lead humanity to the era of technological singularity. Due to the impossibility for a man to refuse to use the technology, he must follow the principles of measure in everything and the middle way in its development and use.