This study aimed to determine the prevalence of depressive disorder and its association with perceived social support among patients with HIV attending the Infectious Disease Clinic in HTJS. Methods: A cross-sectional study was conducted, and systematic random sampling method was employed for the selection of participants. Socio-demographic and clinical details were obtained through a self-rated questionnaire and participants’ medical records. Depressive disorder was screened and diagnosed using the Mini International Neuropsychiatric Interview (M.I.N.I.) and perceived social support was determined using the Multidimensional Scale of Perceived Social Support (MSPSS). Appropriate statistical analyses were used to determine the prevalence of depressive disorder and its association with perceived social support. Results: A total of 99 patients participated in this study. The mean age of participants was 38.16 ± 1.01 years, and the majority of participants were male (69.7%). Most of the participants were Malay (58.6%), followed by Indians (20.2%), Chinese (17.2%) and others (4.0%). The majority had completed secondary education (54%), and most were employed (79.8%). Most of the participants were single (45.5%) or married (45.5%). The lifetime and point prevalence of depressive disorder was 24.2% and 17.2%, respectively. About 64.7% of patients with depressive disorder were undiagnosed. Out of the 3 sources of perceived social support, perceived social support from a significant other (OR=0.53, p=0.042, Cl=0.29, 0.98) and perceived social support from friends (OR=0.49, p=0.015, Cl=0.27, 0.87) were found to be negative predictors for depressive disorder. Conclusion: This study reports that the prevalence disorder among patients with HIV in HTJS is higher than that of the general population. Patients without depressive disorder reported significantly higher perceived social support scores. Perceived social supports from significant others and friends were found to be important associated factors for lower depressive disorder vulnerability. Hence, physicians should routinely screen for depressive disorder in this vulnerable group and explore and mobilize their social support to reduce patients’ vulnerability to develop depressive disorder. ASEAN Journal of Psychiatry, Vol. 18 (1): January – June 2017: XX XX.