This paper links the discussion on nanotechnology to the discussion on fictionality. following the hypothesis that it could be useful to insight into this complex issue. Both nanotechnology and (non)fiction are regarded as terms marking a general challenge for thinking about the future. Documents that talk about visions, scenarios, imagination or Science Fiction with respect to nanotechnology argue more or less explicitly about fictionality. By investigating relations between nanotechnology and fiction, relying upon arguments from Science and Technology Studies and the philosophy of science, fictionality appears as a technical term bounded to terminologies that structure discussions and statements on nanotechnology. The main part of the paper presents different concepts of the relation between nanotechnology and fictions, starting from a close reading of documents from STS and the philosophy of science. Additional considerations focus on fictionality with respect to the debate on Genetically Modified Organisms. By investigating documents in an interdisciplinary semantic framework and by confronting their different propositions and conclusions, this paper tries to understand the relationship between fiction, scenarios, computer simulation and nanotechnology.