Objective To formulate an optimal treatment for patients with acute organophosphorus pesticide poisoning through the evidence-based approach. Methods Based on the clinical questions raised from a real-life patient of acute organophosphorus pesticide poisoning (OP poisoning) in Emergency ICU (EICU), we searched ACP journal club (1991-April, 2006), The Cochrane Library (Issue 1, 2006), MEDLINE (1966-May 2006) and Chinese Biological Medical Database(1978-May 2006) for systematic reviews , clinical randomized controlled trials, cohort and case-control studies using the keywords of “organophosphorus compounds, poisoning, insecticides, oximes, cholinesterase reactivators, and intermediate syndrome”. The quality of the included studies was assessed. Results One Cochrane systematic review and one meta-analysis were included. These two studies concluded that there was no clear evidence on the benefits of oximes for acute organophosphorus pesticide poisoning. Based on the current evidence, integrated with clinical expertise and the patients’ values, the oximes were not used for this patient, only low-dose atropine was administered with other supportive therapies. After one week of treatment, the patient was discharged since her vital signs were stable and clinical symptoms were relieved. Conclusions The appropriate management for acute organophosphorus pesticide poisoning has been formulated with the approach of evidence-based medicine. Large-scale, methodologically-sound trials are required.