The influence of Ca(ClO)2 on performance of simultaneous desulfurization and denitrification of urea aqueous solutions were investigated in the self-designed small-scale bubbling reactor, and kinetics parameters and equations of simultaneous desulfurization and denitrification of urea/Ca(ClO)2 were calculated through analyzing reaction products. The results show that with additive concentration raised, desulfurization efficiency is not dramatically increased, denitrification efficiency is increased by a big margin, but the increase rate of denitrification efficiency become slower when the amount of additives is more than 0.2%, and the reaction order of urea consumption rate equation and ammonium ions formation rate equation is zero, the equations can be expressed by linear equations, Ca(ClO)2 does not change reaction order, but increase reaction rate and reaction rate constant.