This work deals with a numerical study on forward-facing steps situated in a supersonic flow. The primary aim of this paper is to examine the sensitivity of the velocity, density, pressure and temperature due to step-height variations of such forward-facing steps. Effects on the flowfield structure due to variations on the step height have been investigated by employing the Direct Simulation Monte Carlo (DSMC) method. The studied parameter contours for various values of step heights and profiles in three different sections of the channel are obtained. The results indicate that the fluid flow and temperature characteristics considerably depend on the step heights. The results was also compared with previous published works which showed excellent agreement.