Fluorescence microscopy of testis sections and confocal microscopy of seminiferous tubule preparations were used to follow binding of  FITC-labeled lectins [Wheat Germ Agglutinin    (WGA), Concavalin A (ConA),  Dolichus biflorus Agglutinin (DBA), Pisum sativum Agglutinin (PSA), Ricinus communis agglutinins (RCA60 and RCA120) and Ulex europaeus Agglutinin (UEA1)] to glycoproteins of spermatids of the Golden Hamster (Mesocricetus auratus) during their differentiation. WGA, ConA, RCA120 and PSA binding first appeared on the Golgi apparatus of spermatids in step 2 of spermiogenesis, during which the Golgi apparatus is located near the nucleus. Lectin binding was found closely associated with a cap lying on the nucleus during steps 4-7 of spermiogenesis. The binding was associated with the developing acrosome during the subsequent acrosome phase (steps 8-13) and maturation phase (steps 14-17). UEA1 bound at steps 5, but was inapparent by step 14, indicating that fucose did not become a major component of the acrosomal membrane. The acrosome of hamster epididymal spermatozoa bound WGA, ConA and PSA whereas UEA1 demonstrated very weak acrosomal staining.