Traumatic brain injury (TBI) remains a global health problem with cognitive impairments that can affect an individual’s life. Although there is still no effective treatment for TBI sequelae, virtual reality (VR) technology shows promising results as a training tool to improve cognitive functions. Nonetheless, using a head-mounted display (HMD) device can induce cybersickness. Objective. To assess the feasibility of immersive VR cognitive training on EF and provide insights for a definitive trial. We aimed to assess the tolerability of TBI patients after prolonged use of a HMD. Also, as an exploratory analysis, we evaluated changes in cognition, including executive function, memory, and processing speed after the intervention. Methods. A prospective, single-arm, quasi-experimental study was performed to analyze the feasibility of twelve 20-min sessions of immersive VR over four weeks in patients with sustained TBI. Neuropsychological assessment was applied at baseline (T1), post-intervention (T2), and a three-months follow-up (T3). The Simulator Sickness Questionnaire (SSQ) was administered at the end of each session to evaluate the safety of the intervention. Results. Thirteen participants of mean age 34.86 (11.12), with moderate to severe TBI and average of 305.23 (51.23) days post-trauma were included. Patients showed improvements in EF between T1 and T3 (p = 0.02) and low scores in the SSQ (mean score = 4.33, SD = 4.06). Conclusions. The present VR intervention showed to be feasible and safe for patients with TBI to use a HMD. We also observed positive effects on EF and future studies should consider a home-based approach.