The kinetics of the thermal degradation of a new semi-aromatic polyamide containing benzoxazole unit (BO6) have been investigated by thermogravimetric analysis (TG). Thermal degradation of BO6 could be accomplished by one step. The corresponding kinetic parameters of the degradation process are determined by using Kissinger and Flynn–Wall–Ozawa methods, respectively. Coats–Redfern method is also used to discuss the probable degradation mechanism of the BO6. The results show that the activation energy obtained from Kissinger method is in good agreement with the value obtained by using Flynn–Wall–Ozawa method. The solid-state degradation mechanism of the BO6 is a decelerated R1 type (phase boundary controlled reaction one-dimensional movement).