Sam Shepard is a well known contemporary American playwright, whose family plays have drawn much public interest. Many literary critics have analyzed his family plays in attempt to study masculinity. This thesis explores the dysfunctionality in Sam Shepard's family plays. Masculinity and dysfunctionality are closely related on many different levels. Psychoanalysis is essential in studying masculinity or subjectivity. Many literary critics have drawn Jacaques Lacan's theory in the discussion of Shepard's plays. Lacan's theory provides an applicable framework in deconstructing the inner landscape of these male characters, which helps to shed light on the rational behind their behavioral problems affecting their familial relationships. While Lacan's model explains their psychological problems, Herbert Marcuse’s theory gives explanation to the characters’ social disorientation. An individual's experience of socially displacement affects his mental soundness and has direct influence on his children. The influence then is carried on in the family line. It discusses the causes of psychological turmoil of his characters and the impacts resulted from these struggles. Three of Shepard's plays, A Lie of the Mind, Buried Child and Curse of the Starving Class, are discussed in detail. The characters in these plays are distanced from society, and all of them experience difficulties in their familial relationships. The male characters are often violent and resort to drinking in order to escape from their problems. The three plays depict dysfunctionality in three layers; A Lie of the Mind exhibits dysfunctionality on the individual level, Buried Child shows individual dysfunctionality in relation to the family, and Curse of the Starving Class depicts individual and familial dysfunctionality in relation to society. In A Lie of the Mind, Lacan's model helps to explain the psychological struggles that the male characters are experiencing. This is crucial in understanding the problematic familial relationship. Lacan's theory on the “mirror stage” explains how subjectivity is formed. While Lacan describes the formation of healthy psyche, Shepard's characters are mentally disturbed. Jake in A Lie illustrates exactly this. Then in Buried Child, the family in the play displays the collapse of what Lacan calls the “Symbolic order". This does not only affects the individual, but also his children's and his wife’s psychological well being. The results are traumatic. Moreover, the family in Curse of the Starving Class is socially disoriented. Marcuse's theory, which describes how “surplus repression” arises in a highly industrialized society, can provide explanation for their situation.