Cellulose could be effectively hydrolyzed into reducing sugars with a novel sulfonated carbonaceous solid acid. The catalyst bearing both cellulose catalytic sites (-SO3H) and binding sites (-Cl) was synthesized by one-pot carbonization of sucralose with p-toluenesulfonic acid, bypassing the use of concentrated sulphuric acid and without any post-modification. Influences of reaction time and temperature, water content in ionic liquid, dosage of catalyst and substrate on the yield of total reducing sugars (TRS) from cellulose were investigated. A maximum TRS yield of 67.6% was obtained in the 1-butyl-3-methyl imidazolium chloride at 130 degrees C in 60 min, which was much higher than that hydrolyzed by the -Cl free solid acid (36.1%). The excellent catalytic performance of the prepared solid acid can be attributed to the synergic effect of -SO3H and -Cl groups. This work provided a green method to synthesize sulfonated carbonaceous solid acid for efficient conversion of biomass into biofuels.