This paper presents an experimental study of the vibration variability of adhesive free multi-layered timber beams (AFLTB). AFLTB are obtained by stacking several oak layers assembled through normal wood dowels (NWD) or compressed wood dowels (CWD). The mechanical properties of these natural materials, namely the elasticity moduli and the density which drive the vibration behaviour, exhibit large variability. Moreover, the assembly process may induce an additional source of variability. Consequently, taking into account variability in the analysis and design of AFLTB seems relevant and necessary. All the vibration tests were done using an impact hammer, under free-free conditions. First of all, variability of mass, FRFs, damping and frequencies of individual layers were measured. Then, after assembly, the variability of vibration characteristics of three-layer AFLTB was assessed and analyzed. In addition, finite element models for AFLTB are developed to assess the vibration characteristics of such beams.