The potential damage during the pyrolysis of phenol–formaldehyde (PF) resin in the manufacturing of carbon/carbon components is serious. Accurately modeling the kinetics of the pyrolysis reaction can lead to improvements in processing. To study the pyrolysis kinetics of PF resin, non-isothermal pyrolysis kinetics is investigated using thermogravimetric analysis (ТGA) at controlled heating rates. The research indicates that the pyrolysis process consists of three consecutive and overlapping stages. PEAKFIT was employed to separate overlapping regions, and then pyrolysis kinetic triplet of PF resin is calculated. With the determined apparent activation energies, the most probable mechanism functions and the corresponding pre-exponential factor, the model agrees well with the experimental data.