Abstract: Objective to assess visualization rate of appendix in patients with lower abdominal pain using low dose CT scan examination technology in supine position or left oblique prone position, to improve the diagnosis ability of appendix lesions. Methods 160 patients of clinical examination of appendicitis were randomly divided into two groups and take low dose MSCT scan in supine position or left oblique prone position. The CT findings were analyzed and compared with surgical pathology. Result: Sensitivity, specificity and accuracy of appendix lesion were higher with Left oblique prone scan than supine scan(P < 0.05). Conclusion: Low dose CT scan examination technology in left oblique prone position can obviously improve the detection rate of appendix lesion, was helpful in early diagnose of appendix lesions.