The aim of the study was to evaluate the incidence of brain opportunistic pathologies and survival in patients living with HIV from a Romanian tertiary center. A 15-year prospective observational study of brain opportunistic infections diagnosed in HIV-infected patients was performed at Victor Babes Hospital, Bucharest, between January 2006 and December 2021. Characteristics and survival were compared related to modes of HIV acquisition and type of opportunistic infection. A total of 320 patients were diagnosed with 342 brain opportunistic infections (incidence 9.79 per 1000 person-years), 60.2% males with median age at diagnosis of 31 years (IQR 25, 40). Median CD4 cell count and VL were 36/μL (IQR 14, 96) and 5.1 log10 copies/mL (IQR 4, 5.7) respectively. The routes of HIV acquisition were heterosexual (52.6%), parenteral route in early childhood (31.6%), injecting drug use (12.9%), men having sex with men (1.8%), and vertical (1.2%). The most common brain infections were progressive multifocal leukoencephalopathy (31.3%), cerebral toxoplasmosis (26.9%), tuberculous meningitis (19.3%), and cryptococcal meningitis (16.7%). Patients infected by parenteral mode in early childhood were younger at diagnosis of both opportunistic infection and HIV (p < 0.001 and p < 0.001, respectively), developed more frequently PML (p < 0.001), and had the lowest early (p = 0.002) and late (p = 0.019) mortality rates. Risk factors for shorter survival were age > 30 years (p = 0.001), injecting drug use (p = 0.003), CD4 + < 100/μL (p = 0.007), and VL > 5 log10 copies/mL at diagnosis (p < 0.001). The incidence and mortality rate of brain opportunistic infections were high and did not decrease significantly during the study period, due to late presentation or non-adherence to ART.