Posthuman figures are plentiful in contemporary fictional works. Robots, artificial intelligence, genetically modified or augmented beings, and clones: all find their origins in science fiction, and now abound in mainstream culture. These entities embody humanity’s possible evolutions and trigger both enthusiasm and fear. On the one hand, they offer an optimistic perspective on how current human limits could be overcome (such as old age and death, or more generally biological constraints). On the other hand, they also point out the troubling possibility of humanity’s eradication, to be replaced by radically different “posthuman” beings.This dissertation focuses on the fictional representations of the posthuman in contemporary Anglo-Saxon literature in the following novels: the MaddAddam trilogy (published between 2003 and2013) by Margaret Atwood, Never Let Me Go (2005) by Kazuo Ishiguro, Cloud Atlas (2004) by David Mitchell, Accelerando (2005) and Glasshouse (2006) by Charles Stross, and The Stone Gods (2007) by Jeanette Winterson.While they are sometimes characterized by a break in temporal linearity (in postapocalyptic stories), the fictions of the posthuman are also marked by a form of cyclicity (past, present and future converge).Like the cyborg, the figures of the posthuman are hybrid and combine cybernetic or mechanical machines and biological organisms. They exist in a liminal space, and are able to go beyond the dualisms which permeate our way of thinking (male/female, same/other, natural/artificial).Writing the posthuman means considering its multiplicity, and is based on erasure, repetition and rewriting, following the model of the palimpsest.