A sandwich-type polyoxometalate {(TBA)(7)H-3[Co-4(H2O)(2)(PW9O34)(2)]} was immobilized for the first time into the three-dimensional porous metal-organic framework, MIL-101. The composite material Co-4(PW9)(2)@MIL-101 was prepared and the incorporation of the Co-4(PW9)(2) was confirmed using a myriad of solid state methods (FT-IR, FT-Raman, powder XRD, SEM-EDX and ICP analysis). Co-4(PW9)(2)@MIL-101 reveals to be an active, selective and recyclable catalyst for the oxidation of different substrates: geraniol, R-(+)-limonene, styrene and cyclooctane, using H2O2 as eco-sustainable oxidant. The stability and robustness of the heterogeneous catalyst was confirmed by different techniques. The MIL-101 framework demonstrates to be a suitable and efficient support to accommodate catalytically active sandwich-type polyoxotungstates. (C) 2013 Elsevier B. V. All rights reserved.