Microbial production of silver nanoparticles (AgNPs ) synthesis by microbial isolated bacterial strains have been investigated. Four bacterial isolates isolated from soil samples contaminated with petroleum crude oil were used in the present study. Bacterial cell free supernatants extracts were used for AgNPs synthesis. The most efficient bacterial isolate MAM-42 was identified by 16S- rRNA as Pseudomonas aeruginosa with accession No. 3NP0614. P. aeruginosa MAM-42 formed AgNPs with rounded shape in range of 15 -35 nm as indicated by Atomic Force Microscope (AFM). This results revealed that maximum AgNPs production was recorded at 85.0C° after 30min. incubation with 3.0 mM AgNO3 at pH value of 7.0. The synthesized AgNPs was produced by extracellular crude extract have a great biomedical application and represent a future for more therapeutic and pharmacological applications.