Glycosylation has been reported to affect the epitopes of food allergens, however, there are few reports on its role in crab allergen. In the present study, the effect of glycosylation on the IgE-binding activity of tropomyosin (TM), a major allergen in Scylla paramamosain, was investigated. The results showed that TM was a glycoprotein with a 0.2% carbohydrate moiety and contained O-glycan. Moreover, enzymatic deglycosylation of TM by glycosidase had no effect on the IgE-binding activity of TM. In contrast, treatment with periodate resulted in a significant reduction in its IgE-binding activity.