The reaction of isocyanate with alcohols to form urethane is the basics of the polyurethane industry.This thesis focuses on the reaction of 4,4'-methylene-bis(cyclohexyl isocyanate) reaction with alcohols in the presence of a catalyst. The relevance of this study is that it helps us better understand the fundamental chemical kinetics,thus, have better control over the industry processes. HMDI was reacted with ethanol using different concentration of catalyst.It was established that the rate of the reaction increases with increasing catalyst concentration.The reaction occurs according to the pseudo-first order kinetics in excess of alcohol.