Purpose To detect serum specific IgE to crab allergen in different group people with extracted Eriocheir sinensis allergic proteins and to provide laboratorial evaluation for diagnosis and treatment of crab anaphylaxis.Methods Micro titer plates were coated with the allergic proteins extracted from crab.A total of 1907 serum samples from 3 group people were detected for specific IgE to crab allergens with indirect ELISA.The serological IgE level of different group people allergic to crab food wag compared and analyzed.Results 203 individuals were serum specific IgE positive in the detected 1 907 serum samples,and the positire rates Wag 10.65 percent(203/1 907).The statistical analysis showed that the difference of serum IgE positire rates among the 3 group people wag very significant(P＜0.01).Conclusion The detection of serum specific IgE using allergic proteins extracted from crab has diagnostic meaning,since it can be used as laboratorial evaluation for clinical diagnosis and treatment of crab anaphylaxis.