Objective: The objective of this study is to evaluate the effectiveness, feasibility, and clinical relevance of extended reality (XR) technologies for neurocognitive assessment. Methods: A systematic review of published literature on augmented reality (AR), mixed reality (MR) and fully immersive virtual reality (VR) technologies for neurocognitive assessment was conducted. Studies were included if they evaluated XR for assessing neurocognitive domains, with outcomes related to diagnostic accuracy or usability. Results: 28 studies met the inclusion criteria. VR-based tools (n = 26) were the most commonly utilized, offering immersive environments for assessing several cognitive domains including memory, attention and executive function. AR applications (n = 2) were less frequently utilized but showed promising potential in cognitive impairment detection. No studies utilized MR technology for assessing neurocognitive functions. XR technologies were found to be more sensitive, ecologically valid, and engaging compared to traditional assessment tools. Discussion: XR technologies offer a transformative approach to neurocognitive assessments by providing immersive, interactive environments that go beyond the limitations of traditional methods. Despite their potential, XR technologies face limitations such as high costs and technical challenges like motion sickness. Future efforts should focus on improving accessibility, user interfaces, and incorporating social and emotional dynamics to create more realistic assessments.