Abstract： Objective To study correlation between the clinical classification and outcome of acute paraquat poisoning. Method A total of 43 patients subjected to acute paraquat poisoning admitted from January 2005 to September 2009 were retrospectively studied. A clinical classification was made based on the criteria of damage severity of involved organs in these patients within 24 hours after admission, and the correlation between classification and outcome of patients was analyzed with Fisher s exact probabilities analysis. Results Thr clinical types were classified within 24 hours after admission: mild type (n= 6), all patients survived; moderate type (n= 20),nine patients died (45.0% mortality),and severe type(n= 17), 16 patients died (94.1% mortality). The Fisher's exact probabilities analysis demonstrated significant differences in mortality among different clinical types (exact P ＜ 0.01). There was no difference in mortality between mild and moderate type (exact P= 0.063). The mortality rate of mild type was lower than that of the severe type (exact P=0.01), and the mortality rate of mod-erate type was lower than that of the severe type (exact P=0.002). Conclusions This method of classification can be used to distinguish various degrees of intoxication,and has a correlation with prognosis of patients.