Malt bagasse (MB) is a valuable and abundant by-product, representing 85% of the total residues (about 20 kg of wet MB per 100 liters of beer) in the brewery industry. The objective of this study was to compare the chemical composition of MB from two brewery industries: MB1: “pilsen” type beer residue, predominantly composed of barley malt, and MB2: “Weissbier” type beer residue, predominantly composed of wheat malt. MBs dry matter was chemically characterized according to the: protein, lipid, ashes and total carbohydrates contents, based on the AOAC methods. Moreover, the fractions of cellulose, hemicellulose and lignin in the lignocellulose were also determined based on the values of insoluble fibers in acid (ADF) and in neutral detergent (NDF). MB2 presented significantly (p<0.05) higher protein content (MB1= 21.18 ± 0.09% × MB2= 25.23 ± 0.09%), lipid content (MB1= 8.30 ± 0.06% × MB2= 9.04 ± 0.01%) and ashes content (MB1= 3.75 ± 0.05% × MB2= 4.24 ± 0.13%), when compared to MB1. However, MB1 had a higher (p<0.05) carbohydrate content (MB1= 50.21 ± 0.34% × MB2= 47.00 ± 0.30%), when compared to MB2. Moreover, the fibrous fraction of MB1 showed higher (p<0.05) cellulose content (MB1= 16.09 ± 0.06% × MB2= 14.71 ± 0.10%), higher hemicellulose content (MB1= 29.89 ± 0.13% × MB2= 27.68 ± 0.20%) and higher (p<0.05) lignin content (MB1= 20.97 ± 0.11% × MB2= 19.22 ± 0.24%). These differences in the compositions are mainly due to the different brewing formulations studied. The results showed a great potential of both MBs for the production of value-added products, such as bioethanol. Furthermore, the high contents of fibers and proteins in MB make it a very interesting ingredient to be incorporated in food formulations with the aim of improving their nutritional value.