The Adomian decomposition method (ADM) is employed in this paper to investigate the free vibrations of a stepped Euler-Bernoulli beam consisting of two uniform sections. Each section is considered a substructure which can be modeled using ADM. By using boundary condition and continuity condition equations, the dimensionless natural frequencies and corresponding mode shapes can be easily obtained simultaneously. The computed results for different boundary conditions, step ratios and step locations are presented. Comparing the results using ADM to those given in the literature, excellent agreement is achieved. (C) 2010 Elsevier Inc. All rights reserved.