The present investigation was undertaken with the objectives to study the biochemical composition of Pleurotus florida grown on different straw substrates and activity of cellulolytic enzymes produced by Pleurotus florida under in vitro conditions. The results revealed that, the biochemical composition of P. florida raised on three straw substrates exhibited higher percentage of fat () on soybean straw followed by wheat () and paddy straw substrate () on dry weight basis. | Biochemical composition of different straw substrates and activity of cellulolytic enzymes produced by Pleurotus florida under in vitro Conditions