The photocatalytic degradation of formaldehyde in a sound-magnetic assisted fluidized bed (SMFB) was investigated using Degussa P25 catalyst and Fe3O4 particles as the fluidized media. The effects of magnetic induction, sound pressure level, and sound frequency on the degradation rate of formaldehyde were investigated. Compared with fluidized bed (FB), sound assisted fluidized bed (SFB), magnetic assisted fluidized bed (MFB), SMFB could enhance the degradation efficiency of formaldehyde effectively. Experimental results showed that the degradation efficiency of formaldehyde increased with increasing magnetic induction and sound pressure level. The degradation efficiency of formaldehyde increased with increasing sound frequency ranging from 50 to 100 Hz, further decreased with increasing sound frequency from 100 to 150 Hz. Moreover, it was found that the reaction kinetic fitted the pseudo-first-order kinetic equation, which provided a detailed kinetic understanding of photocatalytic degradation of formaldehyde in SMFB. C) 2012 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights reserved.