Background: This study was aimed at determining the levels of anxiety, depression and psychological distress among patients presenting for the first time to the general outpatient department at a teaching hospital in Lagos, Nigeria. Methods: Participants were randomly selected while waiting to see the medical officers at the general outpatient department of Lagos University Teaching Hospital, Ikeja, Lagos, Nigeria. They were screened with twelth version of the General Health Questionnaire (GHQ-12), Self-rating Depression Scale (SDS) and State-Trait Anxiety Inventory (STAI). Results: There were more female participants 178 (53.4%) and about half of them were single 179 (57.9%). The age of the participants ranged from 12 - 92 years with a mean of 32.2 + 13.6. Of the total participants, 210 (67.9%) manifested with probable psychological distress, 145 (46.9%) manifested with anxiety and 49 (15.7%), 10 (3.2%0 and 19 (6.1%) suffered from mild, moderate and severe depression respectively. Psychological distress among participants was significantly associated with anxiety (P < 0.05). Anxiety was statistically significantly associated with depression (P < 0.05). Thus, participants who had anxiety were more at risk of being depressed. Conclusions: There is a need for active collaboration between the mental health team and the medical officers working at the general outpatients’ department and primary healthcare settings due to the high levels of psychopathology seen at these settings. We therefore suggest that medical officers working at these setting acquire the skills of mental health screening and evaluation