The isothermal cure of vinyl ester resins proceeds through several processes such as gelation, vitrification and behavior similar to autocatalysis. The cure kinetics of vinyl ester resins with poly(methyl methacrylate) or poly(vinyl acetate) as a low profile additive was analyzed by introducing a new kinetic model based on those processes. After the parameters in the model were determined through dynamic differential scanning calorimetry, the kinetic model was compared with isothermal DSC results. By using this model time-temperature-transformation (TTT) cure diagram was also plotted. The gelation time and vitrification time calculated from the kinetic model show good agreement with experimental values. Vinyl ester resin with a compatible low profile additive (i.e., PVAC) showed faster gelation but slower vitrification than the vinyl ester resin with an incompatible low profile additive (i.e., PMMA).