Purpose <p>Cancer-related cognitive impairment is one of the symptoms of neurotoxicity among patients receiving chimeric antigen receptor (CAR) T cell therapy. Evidence of the overall estimated prevalence of cancer-related cognitive impairment following CAR T-cell therapy among patients with hematologic malignancies at short-term and long-term follow-ups is lacking. This review aimed to summarize the cognitive functioning status and estimate the prevalence of cancer-related cognitive impairment at follow-up within 1&#xa0;month, 1 to 12&#xa0;months, and &gt; 12&#xa0;months after CAR T cell therapy.</p> Methods <p>PubMed, Cochrane Library, EMBASE, CINAHL Plus, Web of Science, and PsycINFO via ProQuest from inception through August 2024. Studies that reported on cognitive impairment among patients receiving CAR T cell therapy with valid measures were included. Data on cognitive impairment prevalence were pooled using a random-effects model.</p> Results <p>In total, 16 studies involving 1407 patients were included. The pooled cancer-related cognitive impairment prevalence rates assessed using neuropsychological tests at the follow-up timepoints (&lt; 1&#xa0;month, 1–12&#xa0;months, and &gt; 12&#xa0;months) were 24% [95% prediction interval (PI) 16–33%], 33% (95%, PI 9–64%), and 35% (95%, PI 23–48%), respectively. The prevalence estimates assessed using other measures were ranging from 4 to 38% across different timepoints. The leave-one-out meta-analyses quantified the impact of these potential outliers on the estimation of the overall prevalence.</p> Conclusions <p>The findings stress the importance of developing targeted interventions to prevent or manage cognitive impairment in cancer patients during both short-term and long-term follow-up periods. This review also highlights the need for further research in this area to improve our understanding of the disease mechanisms and implement preventive strategies for managing cancer-related cognitive impairment.</p>