Objective To explore the risk factors of delirium in older adults in the Emergency Department. Methods Studies were retrieved from CNKI,VIP,SinoMed,Wanfang Database,PubMed,Web of Science,and Cochrane Library from their inception to October 6,2021. Those observational studies evaluating the influencing factors of delirium in elderly patients in the Emergency Department were included. Two investigators independently screened the studies,extracted the data and evaluated the risk of bias of the included studies,RevMan 5.3 software was used for meta-analysis. Results A total of 25 articles involving 17,497 Emergency Department patients were included,including 1,843 patients(10.5%) with delirium. Meta-analysis showed that the risk factors for delirium in elderly patients in the Emergency Department were advanced age(>75)(OR=1.16,95%CI:1.05~1.29),female gender(OR=1.29,95%CI:1.08~1.54),years of education<6 years(OR=2.80,95%CI:1.60~4.89),living in a nursing home(OR= 3.40,95%CI:1.85~6.28),altered mental status(OR=13.86,95%CI:8.84~21.72),history of delirium attacks(OR= 3.85,95%CI:2.22~6.66),frailty(OR=1.63,95%CI:1.01~2.64),presence of cognitive impairment(OR=2.39,95%CI:1.14~5.01),visual impairment(OR=2.08,95%CI:1.33~3.25),hearing impairment(OR=1.90,95%CI:1.07~3.35),stroke or history of cerebrovascular accident(OR=1.70,95%CI:1.37~2.11),combined dementia(OR=5.14,95%CI:3.87~6.84) and epilepsy(OR=2.69,95%CI:1.41~5.14). The publication bias of the study was not significant. Conclusion Delirium in elderly patients in the Emergency Department is associated with a variety of factors,and early identification of delirium syndrome risk factors by nursing staff and implement individualized intervention timely.