Objective: To analyze the correlation between behavior and lifestyle factors and anxiety symptoms of left-behind children, and to provide evidence for mental health intervention of left-behind children. Methods: 1 188 children aged from 13 to 18 (617 non-left-behind children and 571 left-behind children) in B County of Shangrao City, Jiangxi Province were evaluated with Generalized Anxiety Disorder Scale (GAD-7). Meanwhile, physical activity, TV watching time, computer usage time, dietary behavior, sleep and other behavioral lifestyle factors of left-behind children were investigated by questionnaire. Results: The detection rate of anxiety among left-behind children (66.0%) was higher than that of non-left-behind children (60.5%). The detection rates of mild, moderate, and severe anxiety were 26.3%, 15.4% and 24.3%, respectively. Under the condition of controlling age and gender, Logistic regression analysis showed that left-behind childrens anxiety symptoms and computer usage time>3 h/d (mild anxiety, OR=3.00, 95%CI=1.27-4.16; moderate anxiety, OR=4.09, 95%CI=1.55-10.78; severe anxiety, OR=3.44, 95%CI=1.46-8.11), mobile phone usage time >3 h/d (mild anxiety, OR=4.93, 95%CI=2.71-8.94; moderate anxiety, OR=5.93, 95%CI=2.98-11.79; severe anxiety, OR=7.11, 95%CI=3.85-13.15), skipping breakfast behavior (moderate anxiety, often skipping, OR=6.09, 95%CI=1.59-23.36; severe anxiety, often skipping, OR=5.49, 95%CI =1.68-7.97, sometimes eat breakfast, OR=2.68, 95%CI=1.10-6.53) was positively correlated; with appropriate sleeping time (moderate anxiety, OR=0.28, 95%CI=0.13-0.60) was negatively correlated. Conclusion The unhealthy behavior and lifestyle of left-behind children may be a potential risk factor for anxiety symptoms.