［Objective］To prepare organic polysilazane（PSN）composite coatings with excellent high temperature resistance at lower curing temperatures.［Methods］By introducing silane coupling agent modified silicon carbide（SiC） particles as heat-resistant reinforcement phase，the reaction kinetics of PSN in the thermal crosslinking reaction process were investigated and gradient programmedtemperature curing process was developed to evaluate the curing efficiency and high temperatureresistance of PSN based composite coatings with different SiC addition amounts at lower curingtemperatures（100-200 ℃）.［Results］The PSN composite coatings were prepared using the curing process of 130 ℃/2 h，150 ℃/2 h，180 ℃/2 h，and 200 ℃/2 h，while the addition of modified SiC significantly improved the high temperature resistance of the PSN composite coating. Notably，the high temperature resistance of PSN composite coatings increase with the addition of modified SiC，among which the PSN composite coating with 5% modified SiC content has the best thermal stability，the maximum temperature tolerance of the coating exceeds 400 ℃ and there are no cracks or defects on thesurface after the heat treatment at 400 ℃.［Conclusion］The modified SiC reinforced PSN compositecoatings prepared by gradient programmed temperature curing process can significantly reduce thecuring temperature of PSN coatings while effectively improving their high temperature resistance limit.