Objective: To investigate the prevalence of metabolic syndrome (MS) and to explore the relationship of MS with screen time (ST) among children aged 6-13 years in Guangzhou, China. Methods: A total of 4 523 children aged 6-13 from 5 primary schools in Guangzhou were selected using stratified random cluster sampling method. Questionnaire was used to assess children’s basic demographic characteristics and ST. Children’s height, weight, waist circumference and blood pressure were measured objectively, and their blood glucose, triglyceride and high-density lipoprotein-cholesterol were tested. -Chi-square test was performed to compare the prevalence of MS in children among different ST levels. Logistic regression model was used to explore the association between ST and MS. Results: The prevalence of MS in children was 2.4%, and that among boys (3.0%) was higher than in girls (1.7%, P=0.01). children were classified into three groups according to duration of ST: low ST (less than 1 h), moderate ST (1-2 h), high ST (higher than 2 h, 9.0% of total participants). Prevalence of central obesity, triacylglycerol and MS in high ST group was significantly higher than children with low ST(P<0.05). Children with high level of ST showed higher risks of central obesity (OR=1.43, 95%CI=1.04-1.96) and MS (OR=1.94, 95%CI=1.11-3.40) compared with low-level ST group. Conclusion Higher level of screen time associates with an increased risk of MS in children, which suggest the importance of effective early intervention.