Objective: To study the associations of rs 7498665 polymorphism located in the SH2B adaptor protein 1 gene with obesity related phenotypes in Chinese children and adolescents, and to explore the gene lifestyles interactions. Methods: Anthropometric measurements and lifestyles investigation were conducted in 3 305 children and adolescents aged 7-18 years old recruited from Beijing. The matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI TOF MS) was used to genotype rs 7498665 polymorphism. Multiple Logistic and linear regressions were performed to analyze the associations of rs 7498665 with obesity and obesity related phenotypes by different levels of physical activity and diet behavior. Results: The G allele of rs 7498665 polymorphism showed 37%, 101%, 45% and 64% high risk of obesity in population groups with unhealthy dietary intake, not eating breakfast daily, high consumption of sugar sweetened beverages or not daily moderate to vigorous physical activity ( P <0.05). In the further analysis, the G allele of rs 7498665 polymorphism was associated with obesity in population with unhealthy lifestyle score ( OR=1.63, 95%CI=1.23-2.17, P <0.01). There were similar results with obesity related phenotypes, with the genecomprehensive lifestyle behaviors interactions were significant ( P gene×lifestyle behaviors <0.05). Conclusion The present study suggests the interactive effect of rs 7498665 polymorphism located in the SH2B1 and unhealth lifestyle on childhood obesity and related phenotypes.