The proximate, phytochemical, mineral and 203.072±2.32 in ORS' Magnesium: 27.2± 2.8 in ORS to 8.8 ±1.39 in PAS, Potassium: 352.3 ± 2.32 in ORS to176.1 ± 0.54 in PAS, Sodium: 12.67 ±0.58 in ORS to 9.2 ± 02 in ANS, Phosphorus: 233.47 ± 1.63 in PES to 158.09 ± 05 in ANS. For heavy metals Andropogon traw contained the highest ppmCadmium (7.18), Zinc, (25.08), Lead, (8.44), and copper, (9.96), than the other straws. Oryza straw contained next highest of zinc, but lead was not present. The result of the investigations were discussed in relation of the usefulness of the straws in the cultivation of the edible mushroom Pleurotus ostreatus var florida.