The manganese(III)-salophen complex has been successfully immobilized for the first time on natural diatomite by a simple procedure. This catalyst was characterized by FT-IR, UV-vis, SEM and elemental analysis. The new catalytic material has been evaluated as oxidation catalyst. Our results show that these composite exhibit significant catalytic activities for alkene epoxidation and alkane hydroxylation using sodium periodate as oxidant. (C) 2008 Elsevier B.V. All rights reserved.