Solid base is a kind of important heterogeneous catalyst for the transformation of various chemicals. Although many different novel solid bases have reported, it is a still challenging process to generate strong basic site on many functional supports due to the high temperature treatment of strong base preparation. In this paper, the strong basic site was successfully generated on hypercrosslinked porous polymers (HCPs) via a reducing group strategy. With the reducing groups on HCPs, the decomposition temperature of base precursor KNO3 could be as low as 320 degrees C. Further investigation illustrated the reducing groups participated in the KNO3 decomposition through a redox strategy. The obtained solid base catalysts showed good oxidation capacity of methylene compounds.