Background:As pain is the most prominent clinical symptom for cancer patients and closely related to other symptoms,it is necessary to have a comprehensive assessment on promising intervention to improve pain management.Methods:A retrospective study of 489 inpatient cancer patients（1081 visits） was conducted by querying the electronic medical record database to test the reliability and validity of the Edmonton Symptom Assessment System.Data from a pilot prospective randomized controlled study on acupuncture for cancer pain was analyzed to validate the Edmonton Symptom Assessment System（ESAS） as the primary outcome in the integrative oncology research.Results:In the retrospective analysis,scores of the numerical rating scale（NRS） and the ESAS total score were significantly correlated（r=0.15,P=0.02）,and the correlation coefficient between NRS and pain sub-scale in ESAS was 0.47（P ＜0.001）.The pilot study showed the proportions of participants experiencing more than a 2-point reduction in NRS at the end of the treatment were 80%（n=12/15） in the acupuncture group and 50%（n=7/14） in the control group,without a significant difference between groups（P=0.13）.For the total scores of ESAS,more responders were found in the acupuncture group（n=13/15） compared to that in the control group（n=7/14）,with no significant difference between groups（P=0.05）.Conclusions:ESAS is suitable for the comprehensive assessment in patients with cancer pain and could be an appropriate outcome measurement in acupuncture research for cancer pain.Trial registration:Registered on 09/07/2018 with ChiCTR1800017023（https://www.chictr/org.cn/edit.aspx?pid=28879＆htm=4）