The multi-walled carbon nanotubes ((MWCNTs) coated with the face-center cubic ZnSe nanoparticles with a uniform and small diameter have been prepared to form MWCNT/ZnSe heterostructures by microwave irradiation. The morphology, loading quantity and size of the ZnSe nanoparticles in the range of 15-50 nm can be controlled easily by adjusting the microwave power, pH value of the initial solution, the molar ratios of the Zn(AC)(2)/MWCNTs and the appropriate complexing agent. The photoluminescence measurement indicates that the MWCNT/ZnSe heterostructures are blue-shifted compared to reported bulk ZnSe. The UV-vis absorption spectra of the heterostructures appears two sharp absorption peaks at 336 and 344 nm, respectively. It was demonstrated that the heterostructures could photodegrade the fuchsine acid in the solution with highly photocatalytic activity. (C) 2008 Elsevier B.V. All rights reserved.