The succession of chitinozoans in the East Baltic P ídolí Series was studied in the Ohesaare, Ventspils D-3, Pavilosta and Dubovskoye (Northern-Gusevskaya 2) drill cores. Some differences in biozonal characteristics were observed between the shallower and deeper facies sections. The lower P ídoli Eisenackitina kerria–Ancyrochitina tomentosa regional Biozone is described from the Ohesaare (Estonia) and Ventspils and Pavilosta (Latvia) cores and the Fungochitina kosovensis global Biozone from the Dubovskoye (Kaliningrad district) core. The middle P ídolí Salopochitina filifera regional Biozone is represented in all studied sections. The upper P ídolí Anthochitina superba global Biozone is described from the Ventspils core, correlating with the range interval of Margachitina sp. in the Dubovskoye core. In the uppermost P ídolí the Ancyrochitina lemniscata regional Biozone is distinguished for the first time in the Ventspils and Dubovskoye cores. All biozones were correlated with regional strati-graphical units, as well as with conodont and vertebrate biozones in the Ventspils core.