Objective We sought a good understanding of the current role of computed tomography (CT) in the diagnosis of small bowel obstruction (SBO).Methods We looked for the best evidence on computed tomography for diagnosing small bowel obstruction by searching MEDLINE/PubMed (1978-April, 2006), SUMsearch (1978-April, 2006), CNKI (1978-April, 2006) and critically appraised the evidence. Results There was powerful evidence supporting the efficacy of computed tomography in the diagnosis of small bowel obstruction. Given the current evidence together with our clinical experience and considering the patient and his family members, values and preferences, computed tomography was done. We confirmed the diagnosis of strangulating small bowel obstruction, which needed immediate operation. Conclusions Computed tomography is a very useful tool for the diagnosis of small bowel obstruction with high sensibility and specificity.