The cashew apple bagasse is a promising agroindustrial residue for biotechnological processes. Thus, by prehydrolysis of the hemicellulose fraction, are released both sugars compounds as inhibitors of fermentation. The aim of the present study was to evaluate the characterization liquor resulting from the acid prehydrolysis before and after the vacuum concentration and treatment with residual lignin. The bagasse was submitted acid prehydrolysis using H2SO4 3% (weight/weight). The prehydrolyzate was concentrated and then treated with lignin residual, for improve the efficiency of the process for subsequent fermentation (production of xylitol). The liquor showed maximum concentrations of xylose, glucose and arabinose (4.5 g/L, 2.9 g/L and 18.52 g/L) and minimum acetic acid, 5-HMF and furfural (0.