In this study, the effects of variation in Si content on the properties of porous MoSi$_2$ fabricated by Self-propagating High temperature Synthesis (SHS) process were investigated. Excessive Si added to the stoichiometric composition of MoSi$_2$ were ranged from 0 to 20 wt%. The preheating process prevented the unstable combustion which might occur because of the decrease in reaction temperature due to the excessive Si. With increasing Si content, the permeability of porous MoSi$_2$ material decreased due to decrease in porosity caused by the volume shrinkage after synthesis. Specific resistivity of the synthesized porous MoSi$_2$ was varied from 0.02 to 0.05Ωㆍcm as a function of the size of Mo powder. The use of excessive Si increased the rigidity due to the binder effect between clusters of MoSi$_2$ particles in case the coarse Mo powders were used to make the preform.