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The current global energy crisis has generated growing interest in looking for alternatives to traditional fossil fuels, presenting lignocellulosic materials as a promising resource for sustainable energy production. In this paper, the calorific values and chemical composition of the trunks, branches, twigs and leaves of five timber species of the semi-arid land of Mexico (Helietta parvifolia (Gray) Benth., Ebenopsis ebano (Berl.) Barneby, Acacia berlandieri (Benth.), Havardia pallens (Benth.) Britton & Rose and Acacia wrightii (Benth.)) were determined according to international standards. The results highlighted the calorific value ranges of 17.56 to 18.61 MJ kg(-1) in trunks, 17.15 to 18.45 MJ kg(-1) in branches, 17.29 to 17.92 MJ kg(-1) in twigs, and 17.35to 19.36 MJ kg(-1) in leaves. The pH presented an acidic trend (3.95-5.64). The content of mineral elements varied in trunks (1.09%-2.29%), branches (0.86%-2.75%), twigs (4.26%-6.76%) and leaves (5.77%-11.79%), showing the higher proportion in Ca (57.03%-95.53%), followed by K (0.95%-19.21%) and Mg (0.88%-13.47%). The highest amount of extractives was obtained in the methanolic solvent (3.96%-17.03%). The lignin recorded values of 28.78%-35.84% for trunks, 17.14%-31.39% for branches and 20.61%-29.92% for twigs. Lignin showed a moderately strong correlation (r = 0.66) with calorific value, but the best mathematical model was registered with the calorific value depending on the pH and lignin (R-2 = 58.86%).