Objective·To describe the level of multiple symptom distress and physical activity in children and adolescents with cancer,analyze symptom distress profiles,and explicit the relationship between latent profiles and physical activity.Methods·From November 2021 to March 2023,the convenient sample method was used to recruit children and adolescents with cancer aged 10-18 years old,who had been treated for more than 1 month in the Departments of Hematology/Oncology,Shanghai Children's Medical Center and Xin Hua Hospital,Shanghai Jiao Tong University School of Medicine.The questionnaires,including General Information Questionnaire,Memorial Symptom Assessment Scale 10-18(MSAS 10-18)and Modified Chinese Version of Children's Leisure Time Activities Study Survey(CLASS-C),were used.Latent profile analysis was used to identify whether the level of multiple symptom distress in children and adolescents with cancer was population heterogeneity and its explicit characteristics.Whether there were differences in physical activity levels among different profiles of symptom distress was also analyzed.Results· A total of 165 valid questionnaires were collected,with an effective response rate of 91.7％.The symptom distress scores of the top five occurrence rates of symptoms in children and adolescents with cancer were lack of energy with a median of 1(1,2)point,nausea 1(1,2)point,lack of appetite 2(2,3)points,sweat 1(1,2)point,and pain 1(1,2)point.The physical activity level of the patients was mainly light,with a median of 2 530.00(1 577.50,3 721.00)min/week,and moderate to vigorous physical activity was relatively lower[70.00(10.00,197.50)min/week].The patients with cancer could be divided into two latent profiles:"high fatigue-high nausea-high hair loss-high sleepy"and"high fatigue-low nausea-low vomiting-low sleepy",which were named as high symptom distress(n=47,30.6％)and low symptom distress(n=l 18,69.4％)separately.Multivariate Logistic regression analysis showed that patients with acute lymphoblastic leukemia were more likely to be classified as high symptom distress group,and outpatients in the latest hospital visit were more likely to classified as low symptom distress group(both P＜0.05).In addition,patients with high symptom distress had a higher level of light physical activity(P＜0.05),and had a lower level of moderate to vigorous physical activity,but the difference was not statistically significant.Conclusion·There is population heterogeneity in the multiple symptom distress in children and adolescents with cancer.Disease type(acute leukemia)and the way of the latest hospital visit(through outpatient department)are the predictors of symptoms profiles of patients with cancer.Patients who experience high symptom distress have higher level of light physical activity,and perhaps lower level of moderate to vigorous physical activity.