Abstract: Due to poor adaptability to terrain and lack of adhesive force,conventional forestry machinery chasses are prone to wheel-slippage when working in hilly area. Aiming at this problem, a six-wheel driven articulated chassis adopting the principle of profiling terrain was designed with three degrees of freedom (DF). A 3D modeling of forestry chassis with 3-DF articulated body was conducted by solidworks, and was simulated dynamically based on ADAMS for slope climbing and obstacle surpassing with one or two wheels. The performance of obstacle crossing for the forestry chassis with 3-DF articulated body was analyzed through the curves of center of mass for frame and the force between wheels and ground. The simulation showed that the chassis with 3-DF articulated body had good adaptability to the terrain, good traffic ability and flexible steering ability compared with conventional six-wheeled chassis. It can provide enough adhesion force and meet requirements for forestry machinery working in rough hilly area.