Objective:To summarize the best evidence of intracavitary electroencephalogram positioning in peripherally inserted central catheter (PICC) catheterization, and investigate the clinical application of the best evidence.Methods:The literature on the intracavitary electroencephalogram positioning technology in the head end positioning of PICC catheterization was searched through computers on websites or data bases such as Cochrane Library, Infusion Nursing Society, PubMed, ScienceDirect, China National Knowledge Infrastructure, WanFang Data, and VIP. The search period was from the establishment of the database to June 30, 2022. The literature evaluation standards and evidence grading system of the Joanna Briggs Institute Evidence-Based Health Care Center Database were used for literature quality evaluation and evidence grading, summarizing the best evidence. Based on the summary of evidence, the best evidence for intracavitary electrocardiogram positioning guided PICC catheterization was applied to the survey questionnaire. From November to December 2022, a snowball sampling method was used to select 119 PICC nurses for a questionnaire survey.Results:A total of 31 articles were included, consisting of 24 randomized controlled trials, two systematic reviews, four Meta-analysis, and one group standard. We summarized 20 pieces of evidence from 7 aspects, including preoperative evaluation and preparation, catheter delivery process, guidewire connection, guided intracavitary electroencephalogram, timing of catheter withdrawal, optimal position judgment, and effect evaluation. The survey results showed that more than half of the nurses were consistent with the evidence in terms of evaluation and preparation, catheter delivery process, guided intracavitary electroencephalogram, guidewire connection, and timing of catheter withdrawal. The selection of the optimal location judgment was relatively scattered and needed further research.Conclusions:This study provides evidence-based basis for the PICC catheterization positioning using intracavitary electroencephalogram. Based on clinical practice, specialized nurses select the best evidence and develop a management plan that suits individual circumstances, which can ensure maximum patient benefits and continuously improve nursing quality.