Lectin-binding patterns in the accessory olfactory bulb (AOB) of the golden hamster were investigated histochemically with 21 biotinylated lectins. The AOB was divided into rostral and caudal halves according to binding patterns of 16 lectins, WGA, s-WGA, LEL, STL, DSL, BSL-II, DBA, SBA, BSL-I, VVA, SJA, PNA, ECL, UEA-I, Con A and PSA. The caudal half of the AOB was further subdivided into anterior 2/3 and posterior 1/3 by 10 lectins, WGA, s-WGA, BSL-II, DBA, SBA, BSL-I, VVA, SJA, PNA and ECL. In addition, the rostral half of the AOB was subdivided into anterior 1/4 and posterior 3/4 by one lectin, PNA. Thus, the AOB of the golden hamster was divided into 4 divisions on the basis of lectin-binding patterns.