Due to the excessive oil consumption alongside with its possible depletion and the need to find new sources of products with reduced ecological footprint, urges to conduct the research towards to new processes using biomass, especially residues, as sources of raw materials. The acid liquefaction catalyzed by the p-toluene sulfonic acid of sweet potato peel waste was conducted under mild conditions leading to a bio-oil with a conversion of 85 %. The products were analyzed by ATR-FTIR, SEM, GC-MS and elemental analysis. The results have demonstrated the liquefaction of sweet potato peel is achievable and affords a high carbon content bio-oil composed mainly by carbohydrate compounds and esters showing that the liquefied products can be envisaged as a chemical platform for several uses, in particular as biofuel due to its esters content.