Objective: To explore the clinical value of endoscopic ultrasonography in the diagnosis of ulcerative colitis patients. Methods: In our hospital from March 2014 ~2016 year in September admitted 32 cases of ulcerative colitis patients as the research object, all patients underwent endoscopic ultrasonography, and patients were given oral beauty salad diazoxide treatment, compared before and after treatment in patients with intestinal wall thickness, inflammation, and clinical symptom score. Results: After treatment, the total wall thickness of endoscopic ultrasonography in first layer, second layer, third layer thickness decreased significantly than that before treatment, the clinical symptoms improved, the all layers of the intestinal wall in check mucosa thinning, improve. Before and after treatment, the difference was statistically significant (P < 0.05). After treatment, the inflammation of patients recovered well, the levels of inflammation were decreased, compared with the treatment before and after treatment, the difference was significant (P < 0.05). 32 cases before treatment of clinical symptoms score (23.87 + 1.65) points, after treatment score was (9.05 + 0.58) points, before and after treatment, the difference was statistically significant (P < 0.05). Conclusion: Endoscopic ultrasonography can accurately show the changes of the intestinal wall, which is of high clinical value in the diagnosis of ulcerative colitis.