Multi-walled carbon nanotubes/cuprous oxide (MWCNTs/Cu₂O) composite microspheres were fabricated by liquid phase reducing method. The analycis of the functional group, phase and morphology on the samples were characterized by fourier transform infrared spectrometer (FTIR), scanning electron microscope (SEM) and x-ray diffractometer (XRD), which indicated that MWCNTs were combined with Cu₂O to form composite microspheres by vertical and horizontal interspersing. The results showed that compared with the photocatalytic activity of the Cu₂O, the MWCNTs/Cu₂O composite catalyst has more excellent catalytic effect on target organic compound N-formylmorpholine.