This paper reports the macroscopic kinetics of static melting crystallization of caprolactam. The proposed crystal growth model is evaluated by experimental measurements using a pre-designed experimental setup, in terms of the thermal conductivity of caprolactam, the solid-liquid phase interface temperature during crystallization, and the thickness of the crystal layer during the growth of the crystal layer. It was found that the growth of the caprolactam melt crystal layer conforms to the boundary layer heat transfer model. The effects of different coolant temperatures and cooling rates on the growth of the crystal layer are investigated according to a mathematical model, which predicts the growth trend of the crystal layer, and has certain guiding significance for the crystallization process.