A series of nanosized metal–organic frameworks (MOFs) encapsulating different polyoxometalates (POMs) including H3PW4O12, H5PMo12O40, H5PVMo10O40, H5PV2Mo10O40, and H5PV3Mo10O40 was synthesized and used in the selective oxidation of alcohols. The catalyst with a uniform size and morphology offered easy accessibility between substrates and catalyst. At the same time, the MOF ensured that the POM was encapsulated, which could dramatically prevent the assembly of the catalyst. Furthermore, the catalyst showed clear chemoselectivity, which was related to the size or accessibility of the substrates for surface pores. With cetyltrimethyl ammonium bromide aqueous solution as solvent, both improved reaction efficiency and simple recycling of the catalytic system were achieved to afford a green oxidation process.