In order to understand and interpret the large-amplitude hydromagnetic fluctuations in the solar wind plasma, a particle code computer simulation is carried out for a study of nonlinear characteristics of large-amplitude magnetosonic waves in a magnetized high &bgr; plasma. Not only magnetohydrodynamic features such as steepening, shock formation, and soliton production, but also kinetic effects such as Landau damping are observed. The time evolution of a large-amplitude magnetosonic waves is as follows: It first exhibits steepenings because of nonlinear propagation characteristics and shows a forward tilting of its magnetic field profile. Comparison with an existing nonlinear kinetic theory (Barnes, 1979b) for the nonlinear propagation velocity and the steepening time shows a good agreement between the theory and the simulation up to a time of shock formation. The measured Landau damping rate in the simulation agrees well with the linear kinetic theory (Barnes, 1966) even for large-amplitude magnetosonic waves. This is the case when the steepening time is much shorter than the particle trapping time. After a shock condition is reached, solitary spikes are observed from the vicinity of the wave peak which eventually changes the feature of the steepening. The final waveform within the presence computation shows a backward tilting of its magnetic field component.