It was observed that the mycelial growth of Pleutrotus ostreatus occurred on three different liquid media (Czapek’ Dox; Starch Nitrate; Malt Extract), the maximum growth was on Malt Extract. Also, mycelial growth was tested on different proportion of seed + leaf media of date palms. Meanwhile, it was also found that the amount of lipid in seeds was higher than the leaves and also the ash content in the leaves was higher as compared to the seed. The maximum growth was found with 80% seed + 20% leaf in comparison to other media and best mycelial growth was recorded on the 8^th day of incubation. The possibility of using date palm by-products (seeds and leaves) as a substrate for the production of fruiting bodies of P. ostreatus was investigated. The biological sufficiencies were 30.717% and 22.159% for 400gm and 200gm substrate bags, respectively. The obtained results were discussed from the agro-bio-ecological point of view. The results of chemical analysis showed that the fruiting bodies of P. ostreatus essentially contain 0.1gm lipids, 0.047 gm ash and 0.38 gms of fiber / 1 gm dry matter and 9.8 % nitrogen.