In this current work, biodegradation of pesticides by silver nanoparticles were studied was executed using new strain isolate edible mushroom Pleurotus ostreatus and its biologicaly made nano-Silver (AgNPs). AgNPs prepared using the extracts from mushroom were subjected to UV–VIS spectral analysis, FTIR, XRD and SEM. The results of UV-Vis Spectral analysis show SPR peak around at 473 nm, indicates the reduction silver to nanoparticles. FTIR spectrum shows the presence of functional groups such as amine, carboxyl, and hydroxyl corresponds to the silver nanoparticle decrease caused by the mushroom extract. The SEM image of bio-AgNPs prepared from mushroom extract shows the presence of spherical to elliptical shaped agglomerate ranging from 50-200 nm in diameter, with an average size of about 90 nm. Biodegradation potential of Pleurotus ostreatus and silver nanoparticles were evaluated against quinalphos and cypermethrin under three different pH conditions 5, 7 and 9 were investigated. The highest percentage of degradation of 96% was recorded in neutral condition (pH7) in both pesticides by Pleurotus ostreatus and their silver nanoparticles.