Flame spray pyrolysis (FSP) presents a new technique for metal (Pt, Sn, Ru, Nb and W)-loaded metal oxide (MOX) nanoparticle synthesis, which requires only a single step. FSP prepared MOX nanoparticles have recently widely employed for gas-sensing applications. In this work, the performance towards flammable gases of unloaded and metal (Pt, Sn, Ru, Nb and W)-catalyzed metal oxide (ZnO, WO 3, SnO 2 and TiO 2) nanoparticle thick films fabricated by FSP and spin-coating is reviewed, discussed and compared to MOXs prepared by other methods. The gas-sensing characteristics towards H 2, CH 4, C 2H 2, C 2H 4, C 2H 5OH and CO gases of FSP-prepared MOXs are found to be significantly improved in terms of response, response time and selectivity with small Pt, Sn, Ru, Nb and W loading contents ranging from 0.2 to 5 mol% or at.%. In addition, Pt loading on WO 3 and ZnO sensors results in excellent detection performances towards several flammable gases including H 2, CH 4 and C 2H 2. © 2012 Elsevier B.V. All rights reserved.