To understand the curing processes of phenolphthalein–aniline-based benzoxazine (BP-a), the curing kinetics of bisphenol A-aniline-based benzoxazine and BP-a were investigated using non-isothermal differential scanning calorimetry (DSC) at different heating rates. Kissinger, Ozawa, Friedman and Flynn–Wall–Ozawa methods were used to determine the kinetic parameters and built the kinetic models. According to the results, BP-a displays two dominant curing processes, namely the autocatalytic curing process at low-temperature curing (reaction (1)) with the average activation energy of 95.0–98.5 and nth-order curing process at elevated temperature curing (reaction (2)) with the average activation energy of 124.0–126.2 kJ mol−1. Moreover, the predicted curves from the kinetic models fit well with the non-isothermal DSC curve. Non-isothermal differential scanning calorimetry is a promising method to help researchers explore the application of BP-a and other arylamine Mannich bridge structures containing polybenzoxazines.