Abstract: Background and Objective: Crop production provides a range of agro-industrial by-products and crop residues that have been utilized by ruminants and non-ruminants. However, they are also potential sources of methane emission. Moreover, limited information is available on the methane production profiles of these by-products and crop residues. Thus, this study was conducted to evaluate the chemical, mineral and amino acid compositions and methane production profiles of agro-industrial by-products and crop residues. Materials and Methods: Feed samples of agro-industrial by-products and crop residues were collected and processed and ground to pass 1 mm sieve size. Chemical, mineral and amino acid compositions were analyzed using standard procedures. In vitro gas and methane production profiles were determined according to established procedures. Results: Meat and bone meal (MBM) and fish offal waste (FOW) contained high crude protein (574 and 487 g kg–1 DM, respectively). Calcium and phosphorous concentrations in MBM were 67.6 and 36.1 g kg–1 DM, respectively. Fat content in FOW was highest followed by MBM. Wheat bran had the highest starch (387 g kg–1 DM) and noug seed cake (NSC) the highest iron (4383 g kg–1 DM) and manganese (189 g kg–1 DM). The NSC contained higher concentrations of arginine, cystein, methionine and histidine than those of wheat bran. Methane production was highest (p<0.05) in wheat bran while it was lowest (p<0.05) in FOW. Conclusion: The FOW and MBM might be used as suitable feed combinations with crop residues to mitigate methane emission from the livestock agriculture.