Objectives : Conspiracy theories appear today as a specific collective imaginary. Belief in conspiracy theories seems to have clearly increased during the last decades, partly due to their elaboration and diffusion via social media. A lot of empirical research about conspiracy theories are designed in social and cognitive psychology, but only a few studies adopt a clinical point of view. One reason is that such a clinical approach carries the risk of abusively applying some psychopathological notions to a wide range of the general population, and to a social – and not only individual- construct. This paper aims to promote a psychodynamic approach to conspiracy theories. We argue that this approach allows to studying them as subjective and collective constructs, leaving aside any attempt to make a diagnosis on people believing in conspiracy theories, and any dichotomy between the normal and the pathological. Materials and methods : We discuss tree clinical ways to represent the psychological functions of conspiracy theories : paranoïd ideation, perverse uses, and reaction to traumatic events. As a matter of fact, these clinical notions are often explicitly refered to, or implicitly implied, when psychological motives or functions of belief in conspiracy theories are discussed. We seek to point out the implications of these tree clinical notions and their ability to shed light on conspiracy theories. This leads to discuss their relevance for a differential clinic of the belief in conspiracy theories, allowing to identify the various dimensions of conspiracy theories, and of their subjective uses and functions. Results : Through a psychodynamic understanding of clinical entities, conspiracy theories can be studied as both subjective and collective constructs. In this way, we argue that a psychodynamic approach can avoid the risk of a diagnostical and pathological use of clinical concepts steming from a binary distribution between the normal and the pathological. It rather leads to question along a continuum the various dimensions of conspiracy theories and of the belief in their content. Conclusions : The phenomenon of conspiracy theories seems to emerge fom a wide range of heterogeneous and distinctive cosntructs, uses and attitudes. Belief in conspiracy theories can provide several kinds of psychological benefits, implying various subjective functions and psychic mechanisms. Moreover, in terms of psychological attitudes, we have to clearly distinguish different phenomena : some spontaneous and collective elaborations of conspiracy theories, belief in conspiracy theories, the process of their diffusion, and their political, social and psychological intentional uses. These heterogeneous dimensions raise the risk of undermining any study of this phenomenon considering it as a unidimensional and a unified construct. In this way, we argue that a differential clinic of this conspiracy phenomenon is a methodological need, prior to the design of empirical clinical studies and to the reflexion about preventive actions.