Abstract. The foraminiferal zonation reported here is valid for the marine Oligocene deposits in the Mainz Basin. Thirteen zones and one subzone are defined in the basin facies, which may be correlated biostratigraphically with the current nannoplankton zones and also lithostratigraphically. The zonation for the beach facies, already described by the present author, is incorporated into the scheme. It is possible, therefore, to generate a high resolution foraminiferal biostratigraphical subdivision of the marine Oligocene deposits of the Mainz Basin.