Migrating primordial germ cells ofRana dalmatinaembryos were labelled byDolichos biflorusagglutinin. Confocal microscopy analysis demonstrates the nuclear localisation of the labelling. The glycoconjugate is expressed by primordial germ cells throughout the entire migration process, but it is no longer detectable in late intragonadal primordial germ cells. These data suggest that the a‐N‐acetylgalactosamine‐containing glycoconju‐gates in the nucleus of primordial germ cells may play a functional role in primordial germ cells protection against differentiation during the migration process. The temporal correlation between disappearance of nuclearDolichos biflorusagglutinin positivity and colonisation of the gonadal ridges, may be explained by a change in the functional status of primordial germ cells nuclear glycoconjugates in relation with the onset of primordial germ cells differentiation.