Abstract: Bifurcation and chaos of an axially accelerating viscoelastic belt are investigated.Based on geometry nonlinearity,nonlinear governing equations of motion for the axially acelerating viscoelastic belt are derived by using Hamilton's principle.The partial differential governing equations are truncated to a set of fourdimensional ordinary differential equations based on the first term Galerkin method.The nonlinear dynamical behaviors of the system are numerically identified by using the bifurcation diagrams.The results of numerical simulations indicate that bifurcation and chaos occur in the transverse nonlinear oscillations of the axially acelerating viscoelastic belt.