Background <p>Recently, extended reality technologies have been increasingly utilized in therapeutic and educational interventions for individuals with autism spectrum disorder (ASD). This systematic review and meta-analysis evaluated the effectiveness of extended reality interventions in addressing core deficits and enhancing functional performance among individuals with ASD.</p> Methods <p>A systematic literature search was conducted across six databases—namely, PubMed, Embase, Cochrane Library, PsycINFO, CINHAL, and ERIC—from their inception to August 29, 2024, with no language restrictions. Studies were included if they (1) examined participants diagnosed with ASD; (2) employed an intervention utilizing virtual reality, augmented reality, or mixed reality; (3) used outcome measures related to social functioning, behavior, emotion, cognition, and anxiety; and (4) were published in a peer-review journal. The standardized mean difference (SMD) was employed as the primary effect size indicator, while heterogeneity was assessed using the I² statistic. Additionally, the quality of the included studies was systematically analyzed.</p> Results <p>A meta-analysis of 11 randomized controlled and 20 non-randomized trials was conducted using a random-effects model. The extended reality intervention resulted in significant improvements in social skills (SMD: 0.59, <i>p</i> = 0.04), behavior (SMD: 0.61, <i>p</i> = 0.004), emotion recognition ability (SMD: 0.86, <i>p</i> = 0.0005), and cognitive ability (SMD: 0.92, <i>p</i> &lt; 0.00001) among individuals with ASD.</p> Conclusion <p>This study’s findings substantiate the effectiveness of extended reality interventions for addressing core deficits and enhancing functional performance among individuals with ASD. Therefore, the utilization of extended reality in therapeutic and educational interventions for individuals with ASD is both feasible and promising.</p>