BACKGROUND Antiretroviral (ARV) therapy extends life for persons living with HIV. Antiretroviral treatment (ART) has been rapidly expanding coverage around the world, including in Iran. However, ART drug resistance also rapidly develops with expanding use and limits effectiveness and treatment options. The aim of this study was to monitor the appearance of new mutations conferring HIV pretreatment drug resistance in the treatment of naïve patients with HIV in Iran. METHODS Blood samples were obtained from ARV treatment-naïve patients from 8 different provinces in Iran in 2016 for genotyping for drug resistance mutations. RESULTS Sequences were successfully obtained from 90 specimens. Of these, 2 (2%) mutations conferring resistance to protease inhibitors, 2 (3%) conferring resistance to nucleoside reverse transcriptase inhibitors (NRTIs), and 9 (13%) conferring resistance to non-NRTI (NNRTI) were detected. Any ARV-resistant drug mutation was found in 11 patients (12%). CONCLUSIONS Nearly one in 8 ARV-naïve patients had mutations associated with NNRTI resistance in diverse areas of Iran in 2016. Iranian ARV therapy guideline for HIV could consider non-NNRTI-based first-line therapies and expand routine drug resistance testing before treatment initiation as according to HIV drug resistance recommendations of the World Health Organization.