In this work realized by CIRAD, a specially designed crossed fixed-bed reactor was used to characterize thermal and catalytic tar reduction due to cracking and reforming reactions in fluidized-bed gasification conditions. Coriolis and mass flow meters are used respectively to control water and gas (N2, H2, CO, CO2) contents in the feeding atmosphere. A partial pressure of tar in the atmosphere is obtained by saturating gases at a precisely controlled temperature. The solid bed is deposited on a filtering sheet and can be inert (by using sand) or catalytic. Condensable species were quantified semi-continuously with a gas chromatograph (GC), and then recovered thanks to a cooling device placed after it. Then, a GC coupled with a mass spectrometer is used to quantify species in low concentrations. Gaseous species were continuously quantified by ?GC. In this work, the tar retained is naphthalene, as it is usually considered as a reference of tars present in fluidized-bed gasifiers. Thermal tar destruction is studied by introducing naphthalene in our reactor containing an inert sand bed; catalytic tar destruction is realized using two kinds of well-known catalytic beds: olivine and nickel on olivine. The influence of hydrogen and water contents on tar destruction and on the catalyst lifetime is also considered.