Objective To search and summarize the relevant evidence of early activities for adult patients with ICU acquired weakness, so as to provide reference for medical staff conducting early activities for this population. Methods Relevant guidelines, best practices, systematic review, evidence summary, Meta analysis, expert consensus and high quality randomized controlled trials on the early activity of adult with ICU acquired weakness published from January 1, 2011 to January 31, 2021, in evidence summary database, guideline and association website, relevant primary literature database, were systematically searched. Then two evidence-based nursing trained researchers independently evaluated the literature quality, and the evidences were extracted and summarized from the included high quality literature. Results A total of 13 literatures were included, which were consisted of 2 guidelines, 2 expert consensus articles, 3 systematic reviews/meta analysis and 6 randomized controlled trials. Totally 26 best evidences were developed, including pre-activity assessment, safety standards, activity time, activity intensity, activity stage, activity content and precautions. Conclusion Early activities for adult patients with ICU acquired weakness are safe and feasible. It is suggested that medical staff develop personalized intervention plan according to the summarized best evidence, so as to promote evidence-based practice of early activities, and reduce the poor prognosis of ICU acquired weakness.