Xylose is a hemicellulosic sugar mainly used for its bioconversion to xylitol. Sorghum straw is a raw material for xylose production that has been studied scarcely. The objective of this work was to study the xylose production by hydrolysis of sorghum straw with hydrochloric acid at 122°C. Several concentrations of HCl (2–6%) and reaction time (0–300min) were evaluated. Kinetic parameters of mathematical models for predicting the concentration of xylose, glucose, acetic acid and furfural in the hydrolysates were found. Optimal conditions for hydrolysis were 6% HCl at 122°C for 70min, which yielded a solution with 16·2g xylose/L, 3·8g glucose/L, 2·0g furfural/L and 1·9g acetic acid/L.