Antiretroviral use can reduce the amount of virus in the body and increase the CD4 cell count in people infected with HIV. The success of HIV treatment can be achieved by increasing adherence to taking antiretroviral drugs. The aim of this study was to describe the level of adherence of HIV/AIDS patients undergoing antiretroviral treatment at dr. Agoesdjam Ketapang. The research method used is descriptive research with cross sectional design. Sampling was done by purposive sampling technique with a sample of 45 respondents. Research data were collected through the administration of the Morisky 8-Item Medication Adherence Questionnaire (MMAS-8) questionnaire to HIV/AIDS patients in RSUD dr. Agoesdjam Ketapang. The results showed that the characteristics of HIV/AIDS patients undergoing antiretroviral treatment at VCT Bougenville RSUD dr. Agoesdjam Ketapang is dominated by male patients (78%), patients aged 25-49 years (76%), patients with male HIV transmission factors (38%), patients with high school education (40%), patients who work as private employees (40%), and the majority of HIV/AIDS patients receive artivla therapy (78%). HIV/AIDS patients undergoing antiretroviral treatment at dr. Agoesdjam Ketapang had a high level of treatment adherence (38%), moderate adherence (33%), and low adherence (29%). The conclusion of this study is the level of adherence to treatment of HIV/AIDS patients in RSUD dr. Agoesdjam Ketapang according to high compliance.