Objective To systematically review the effectiveness of early rehabilitation nursing in improving outcomes for traumatic brain injury (TBI). Methods We searched the China National Knowledge Infrastructure, Wanfang, VIP, China Biomedical Literature Database, Cochrane Library, Web of Science, Embase, and PubMed databases for randomized controlled trials evaluating the effectiveness of early rehabilitation nursing (or combined with usual nursing) versus usual nursing for improving outcomes in patients with TBI. The search period spanned from January 1, 2020, to January 1, 2025. Two research evaluators independently screened the literature, extracted data from included studies, and assessed study quality according to Cochrane Collaboration standards. Meta-analysis was performed using Stata 18.0 software. Results A total of 24 studies involving 2088 patients were included, with 1044 patients in each of the trial and control groups. Meta-analysis results showed that, compared with the control group, the trial group had significantly higher post-intervention scores on the Glasgow Coma Scale [mean difference (MD)=2.93, 95% confidence interval (CI) (2.47, 3.40), P<0.001], Activities of Daily Living Scale [MD=12.68, 95%CI (10.33, 15.03), P<0.001], and Fugl-Meyer Assessment of Limb Function [MD=13.04, 95%CI (8.27, 17.81), P<0.001], and lower post-intervention scores on the National Institutes of Health Stroke Scale [MD=−4.37, 95%CI (−5.27, −3.46), P<0.001] and Self-rating Depression Scale [MD=−8.91, 95%CI (−14.26, −3.56), P=0.001], but the difference in Self-rating Anxiety Scale score was not statistically significant between the two groups [MD=−6.62, 95%CI (−13.49, 0.26), P=0.059]. Conclusions Early rehabilitation nursing is effective in improving neurological function, enhancing independence in activities of daily living, alleviating physical impairments, and reducing depression symptoms in patients with TBI. It is worthy of clinical implementation.