The isothermal and nonisothermal crystallization kinetics of nylon 1111 was extensively studied using differential scanning calorimetry (DSC). The equilibrium melting temperature of nylon 1111 was determined to be 188 degrees C. In this article, the Avrami equation was used to describe the isothermal crystallization behavior of nylon 1111. On the basis of the DSC results, the Avrami exponent, n, was determined to be around 3 during the isothermal crystallization process. Nonisothermal crystallization was analyzed using both the Avrami equation as modified by Jeziorny and an equation suggested by Mo. The larger value of the Avrami exponent, n, during the nonisothermal crystallization process indicates that the development of nucleation and crystal growth are more complicated during the nonisothermal crystallization for nylon 1111, and that the nucleation mode might simultaneously include both homogeneous and heterogeneous nucleations. The isothermal and nonisothermal crystallization activation energies of nylon 1111 were determined to be -132 kJ/mol and -121 kJ/mol using the Arrhenius equation and the Kissinger method, respectively. POLYM. ENG. SCI., 49:1366-1374, 2009. (C) 2009 Society of Plastics Engineers