The high genetic variability of HIV-1 and the emergence of transmitted drug resistance (TDR) can impact treatment efficacy. In this study, we investigated the prevalent HIV-1 genotypes and drug-resistance-associated mutations in drug-naïve HIV-1 individuals in Cabo Verde. The study, conducted between 2018 and 2019, included drug-naïve HIV-1 individuals from the São Vicente, Boa Vista, Fogo, and Santiago islands. The HIV-1 gene was sequenced using Sanger sequencing. TDR was identified using the Stanford Calibrated Population Resistance tool, and resistance levels to different drugs were interpreted with the Stanford HIV database. The genetic diversity of HIV-1 was determined through phylogenetic analysis, and epidemiological and behavioural data were collected via questionnaires. Of the 73 participants, the majority were male (52.1%). The CRF02_AG recombinant form predominated (41.1%), followed by subtype G (37.0%). The overall prevalence of TDR was 9.6%. Nucleoside Reverse Transcriptase Inhibitor (NRTI) mutations occurred in 2.7% of individuals, while Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI) mutations occurred in 9.6%. The most prevalent mutations were K103N (5.5%) and M184V (2.7%). No protease- or integrase-associated mutations were found. The high levels of resistance to NNRTIs found demonstrate the need for surveillance of resistance mutations to ensure the efficacy and durability of the current therapeutic regimen, which includes Dolutegravir.