An AlON-SiC-Al2O3 composite was successfully prepared by sintering the phenolic resin-bonded Al-Si-Al2O3 green body at 1700 degrees C in flowing nitrogen. The results show that the major phases of the samples after sintering are alpha-Al2O3, gamma-AlON, and beta-SiC. The reaction mechanism is as follows: At high temperatures, the phenolic resin is pyrolyzed to produce nanoscale, highly reactive residual carbon, which greatly reduced the stability of alpha-Al2O3 fine particles and also improves the wettability of Al(l) to alpha-Al2O3. After a good physical contact between Al(l) and alpha-Al2O3 is achieved, octahedral gamma-AlON is formed by the aluminum thermal nitridation of alpha-Al2O3 fine particles at 1700 degrees C [Al(l)+C(s,resin)+Al2O3(s)+N-2(g)-> Al5O6N(s)+CO(g). Then, the CO(g) released by the reaction is rapidly absorbed by the Si(l) in the system to form stable beta-SiC phase, resulting in a decrease in P-CO, which further promotes the formation and stability of gamma-AlON. The Al2O(g) and Al(g) are the major gas phases in the system at 1700 degrees C, which further participated in the reaction of gamma-AlON formation and makes gamma-AlON grow in a step growth method. The gamma-AlON and beta-SiC stably coexist as reinforcing phases in the samples, forming an AlON-SiC-Al2O3 composite, which has a high cold crushing strength of 389-443 MPa. The reaction model is established.