We have studied the polymerization kinetics of acrylamide in aqueous solution with potassium persulfate as an initiator by using quantitative real-time in situ IR spectroscopy and monitoring the profiles of peaks in the range 1900-850 cm$^$-1/. The conversion of acrylamide was calculated from the disappearance of the peak at 988 cm$^$-1/, which is the out-of-plane bending mode of the=C-H unit, normalized to the C=O stretching peak at 1675 cm$^$-1/, as an internal standard. For reaction temperatures in the range 40-65$^{circ}C$ and initiator and monomer concentrations of 0.9-2.6 mmol/L and 0.5-1.1 mol/L, respectively, we deduced that the rate of monomer consumption follows the relation R$\_$p/=k［K$_2$S$_2$O$\_$8/］$^$0.5/ [Μ］$^$1.35${pm}$0.10/. In addition, we obtained activation parameters from an evaluation of the kinetic data.