Mourning is one of the two concepts that emerged from Freud's article Mourning and Melancholia and is frequently subjected to research. However the concept of melancholia is studied less. Furthermore, melancholia remains in an ambiguous position: sometimes it is attributed to a person's personality pattern and sometimes to a depressive mood or even sometimes to a psychotic structure. From this point of view, in this article, the work of Freud and Lacan (who recontextualized Freud's literature), on mourning and melancholia are examined comparatively. Accordingly, Freud expressed that mourning and melancholia are similar in the loss of a loved object and while mourning is an ordinary response to loss melancholia is an extraordinary position. Faced with Freud's view that mourning and melancholia are similar in terms of lost object, but differ in terms of their functioning, Lacan reconsidered these two concepts through the topological structure of Symbolic, Imaginary and Real. In Lacan's conceptualization, mourning as a process connects the subject to the symbolic order through rituals or ceremonies. The subject who does not/cannot pass beyond this process is stuck in jouissance staying alone with Real in melancholia. In this recent article, several clinical practice and research examples are included following the theoretical examination. Based on this, it is thought that in a state of melancholia, the person is in pain while maintaining a position that one takes as a move from castration to escape and that the way out of this pain is only possible with a symbolic study. However, it is important to study the appearance of melancholia in different subject formations together with today's changing cultural background. As a result, it is thought that how melancholia is expressed in language and its relationship with the defense mechanism related to subject formation of the individual determines the central point in an analytical study.