Abstract: Objective Ulcerative colitis is a chronic non-specific inflammatory disease of the colorectum with obscure etiology,which lesion is confined to the mucosa and submucosa with long and recurrent course of the disease.The purpose of this study is to investigate the changes of inflammatory factors,oxidative stress,bone mineral density(BMD) and bone metabolic indices in children with ulcerative colitis. Methods We selected 58 children with ulcerative colitis who treated in our hospital from April,2015 to August,2016 as observation group,and 40 healthy check-up children as control group to compare inflammatory factors,oxidative stress,bone mineral density and bone metabolic indices between 2 groups. Results CRP,TNF-α and IL-6 levels of observation group were significantly higher than those in control group(P<0.05);NO level of observation group was significantly higher than that in control group(P<0.05),SOD level of observation group was significantly lower than that in control group(P<0.05);BMD of observation group was significantly lower than that in control group(P<0.05),but BGP and BLAP levels showed no significant difference(P>0.05). Conclusion The levels of inflammatory factors and oxidative stress were significantly increased,BMD was significantly decreased in children with ulcerative colitis.Clinical test of the changes of inflammatory factors,oxidative stress and BMD were helpful to the diagnosis and treatment of ulcerative colitis in children.