The effect of the temperature scale on the nonisothermal crystallization of a polypropylene (PP) was studied with the Nakamura equation and a Tobin-type equation for nonisothermal crystallization. The calibration on cooling of differential scanning calorimetry (DSC) data was performed, and the scanning rate dependence of the sample’s thermal resistance was evaluated and taken into account to correct the nonisothermal crystallization data obtained from the DSC measurements. The description of the crystallization was performed with only one varying parameter, which changed regularly with the scanning rate, making possible predictions of real nonisothermal crystallization behavior at intermediate or high scanning rates.