One key point for the development of biomass pyrolysis or gasification in fluidized beds is a better understanding of the biomass particles hydrodynamics inside the bed. The quality of the syngas and the efficiency of the reactor directly depend on the location of the particles at each phase of their conversion (drying, pyrolysis, char gasification/elutriation). Bruni et al.(2002) showed that endogenous bubbles generated by devolatilisation carry the biomass particles to the bed surface. Since Bruni et al.[1] restricted their study to incipient fluidization; this observation should be assessed for turbulent fluidization which is typical for biomass pyrolysers / gasifiers. The hydrodynamics of bubbling fluidized bed has already been investigated by Rao et al. (2011) in hot device through high frequency differential pressure measurements [2]. This method is used in this study to analyze segregation of biomass. The present study achieves segregation experiments with different materiel in cold bubbling fluidized bed (25 cm ID, 20-50°C). Two types of wood are used : beech wood particles with a density of 750 kg/m3 and balsa wood particles with a density of 130 kg/m3 that mimic char particles. The bed is composed of olivine particles (Geldart B classification) with an average particle size of 350 µm and a solid density of 3000 kg/m3. The mass ratio of biomass in bed is between 0 and 10%. Particles are injected over the bed or in the bed just above the air distributor. The comparison allows understanding and assessing the role of the characteristics of biomass property (density, shape) on particles hydrodynamics. The aim of this study is to produce correlations for segregation of biomass in bubbling fluidized bed. Theses correlations could be implemented in pyrolyzer/gasifier models that couples particles hydrodynamics and particles conversion.