Objective Pathological narcissism, described by 2 dysfunctional phenotypic forms–grandiosity and vulnerability–has often been connected to suicidal tendencies in theoretical and clinical literatures. Furthermore, shame proneness has been implicated as a key mechanism that links these 2 constructs. However, empirical evidence for the presumed relationship between pathological narcissism and suicidal tendencies is sparse, and no prior research has investigated the role of shame proneness in this relationship. The objective of the present research was to investigate the complex relations among pathological narcissism, experience of shame, and suicidal ideation in psychiatric outpatients. Method A sample of 250 adult psychiatric outpatients (61% female; mean age 39.15 years) were assessed between January and May 2014. The participants filled out the Pathological Narcissism Inventory, the Experience of Shame Scale, and the Suicide Assessment Scale‐self‐rating. Results Narcissistic vulnerability was found to have unique positive associations with acute suicidal ideation, whereas narcissistic grandiosity exhibited substantially weaker relations with the same construct. Two dimensions of shame–characterological and bodily shame–mediated the relationship between narcissistic vulnerability and suicidal ideation. The mediating role of behavioral shame was not demonstrated. Conclusions Narcissistic vulnerability seems to be more strongly related to suicidal tendencies than narcissistic grandiosity, while experience of shame represents one of the underlying mechanisms of this relationship among psychiatric outpatients. The implications of these findings are discussed in relation to the role of pathological narcissism in the psychotherapeutic management of suicidality.