This paper in Spanish is an early work of my thesis, Ethics of Friendship, which came out in Danish in 2013. The paper takes as its starting point a concept which Friedrich Nietzsche recovered from "philosophical oblivion", namely friendship, and offers an interpretation of its multi-faceted significance in his work. Friendship opens up an ethical way towards self-overcoming, through which each human being, accompanied by another, has the opportunity to reach beyond his or her own limitations. This ethical interpretation of friendship is finally confronted with Nietzsche's own vision of the superhuman and with the philosophical ethics of Hans-Georg Gadamer and Emmanuel Levinas.