A new strategy for the synthesis of jet fuel range branched alkanes with the xylose and methyl isobutyl ketone (MIBK) from lignocellulose was introduced. C-10 and C-11 branched alkanes with low freezing points were synthesized by three steps: (1) the dehydration of xylose to furfural over solid acid catalysts in MIBK/water biphasic solvent systems; (2) solid base catalyzed aldol condensation of furfural with MIBK which was also the most effective extracting solvent in the first step; (3) solvent-free hydrodeoxygenation of aldol condensation product to jet fuel range branched alkanes over Ru/H-ZSM-5 catalyst. Alternatively, oxygenated fuel can also be obtained by the low temperature hydrogenation of aldol condensation product over Ru/C catalyst.