Background: Depression is one of the most frequently observed psychiatric disorder among patients with HIV/AIDS and it has been associated with increased risky behaviors, noncompliance to anti-retroviral treatment, and higher risk for co-morbid survival. Aim: This study was conducted to determine the prevalence and pattern of depression among HIV positive patients on treatment at the ART clinic of UDUTH, Sokoto, Nigeria. Materials and Methods: This was a cross-sectional study among 419 patients (selected by systematic sampling technique) attending the ART clinic of Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria. A structured interviewer-administered questionnaire was used to collect data on the research variables. Data were analyzed using IBM SPSS version 20 statistical computer software package. Results: Two hundred and twenty-seven (54.2%) of the 419 participants were identified as having depression, with 179 (42.7%) having mild depression, 46 (11.0%) having moderate depression, and 1 (0.2%) each having moderately-severe and severe depression. Depression was more prevalent among females (62.9%), those that were unemployed (79.3%), and those who have lived with HIV for 5 years and below (64.5%) as compared to the other groups. Also, depression was less prevalent among those that were married (58.5%) and those who had family support (60.2%) as compared to the other groups. Conclusion: This study showed high prevalence of depression among HIV positive patients attending the ART clinic of UDUTH, Sokoto. These findings underscore the need for HIV/AIDS care providers to make screening for depression and implementation of interventions for its prevention the core components of their services.