Patients with progressive multifocal leukoencephalopathy (PML) in the context of human immunodeficiency virus-acquired immunodeficiency syndrome (HIV-AIDS) show a partial improvement following rehabilitation; however, this improvement is rapidly lost if the patient is not provided with intensive rehabilitation. A 42-year-old patient affected by HIV-AIDS had a clinical worsening within a few months following PML onset, despite being treated with antiretroviral drugs and conventional rehabilitation. He developed severe paraparesis and significant dependency in the activities of daily life. A first cycle of intensive rehabilitation provided the patient with some significant functional outcomes, although he experienced a worsening of the clinical condition after two months of rest, before admission to our rehabilitation unit. We thus sought to evaluate the effects of intensive robot-aided gait training (RAGT) coupled with transcranial direct current stimulation (tDCS). The patient significantly improved when provided with intensive RAGT coupled with tDCS (as per 10-meter Walk Test 10MWT and 6-minute Walk Test 6MWT), and the improvement was maintained at three-month follow-up. As this advanced approach was feasible, safe, and potentially effective, this case suggests that patients with PML-HIV require prolonged multidisciplinary rehabilitation treatment. We can speculate that individuals with PML should also be treated with innovative technology to improve their functional outcomes and therefore quality of life.