The growing popularity of Facebook has prompted much interest in the concept of online self-disclosure. Prior studies have primarily examined this concept from a quantitative perspective, often focusing on how the frequency and pattern of online disclosures relate to personality typologies. This study is the first qualitative exploration of users’ perspectives on their experience of personal self-disclosure on Facebook. The aim of the study was to identify the factors that motivate participants to self-disclose online, the functions that this serves and the impact it has on participants. It involved using a psychotherapeutic analytical framework to conduct a content analysis of the Facebook accounts of 57 Irish third-level students (aged between 18 and 25 years) over a six-month period. Five of these participants, who were subsequently identified as engaging in personal online self-disclosure, were invited to participate in a one-to-one interview. Riessman’s (2010) Narrative Analysis Framework was used to analyse both the online Facebook status updates and the interview transcripts of these five participants, which formed the data for the study. The study findings add new insights to our understanding of the interpersonal and intrapersonal dynamics of online personal self-disclosure. They suggest that the motivating factors can be divided into internal and external motivators. Internal motivators include a desire to entertain, educate or inspire one’s Facebook audience. External motivating factors involve Facebook’s role in encouraging and shaping users’ self-disclosures, which in turn can influence new cultural norms. The findings suggest that online personal self-disclosure may function as an opportunity for users to express their preferred identities and may also be used for processing, managing and expressing difficult emotions and in turn address a users’ psychological need for recognition and validation. The findings also suggest that engagement in online personal self-disclosure often involves intense psychological rumination and feelings of online vulnerability, which may impact users’ psychological wellbeing by triggering experiences of anxiety and preoccupation. As these findings suggest that online personal self-disclosure can be experienced as a catalyst for psychological distress and also act as a mechanism for managing distressing feelings has implications for psychotherapy theory and practice.