In this study, we have shown that biologically synthesized Silver Nanoparticles (Ag-NPs) can effectively inhibit the growth of a clinical isolate of the Acinetobacter spp in vivo. The bacterial strain was isolated from a hospitalized male burnt patient in Sulaymaniyah, Iraq. Initially, Minimum Inhibitory Concentration (MIC) of ampicillin, kanamycin, tetracycline, and azithromycine were determined for the strain using broth microdilution method. The bacterial strain was found to have the highest resistant against azithromycin (400 μg/ml), whereas the MIC for kanamycin, ampicillin and tetracycline were at 200 μg/ml, 100 μg/ml, and 100 μg/ml, respectively. Additionally, Ag-NPs were prepared using the aqueous extract of chamomile (Matricaria chamomilla) flowers. Scanning Electron Microscopy (SEM) image revealed the particles have spherical and irregular flower-like shapes with an average size of 18 ±3 nm based on the X-Ray Diffraction (XRD) spectrum data. Interestingly, the biosynthesized Ag-NPs shown to actively inhibit the growth of the bacterial strain with MIC at 50 μg/ml.