Silver nanoparticles (AgNPs) is the most important nano molecules that have many medical, industrial, and cosmetic application. We study the effect of these particles on the most vital organs such as the liver and spleen in Wister rats.  AgNPs are characterized by using a scanning probe microscope device (SPM). Twenty females were divided into two groups, the control, and the treated group. All treated females gavage 20mg/ml of AgNPs suspension orally for 29 days. The weight of females was 130±5 g. The liver and spleen were used in this study after staining by H&E. The result showed few intracytoplasmic fat vacuoles on liver tissue, on the other hand, the result displayed brown pigment in the sinusoids. The result showed found marked vascular congestion in liver tissue after being treated with AgNPs compared to the control group. The histological examination of the spleen in treated rats showed the presence of brown pigment in the red pulp of the spleen and congestion, and hemorrhage in treated rats. The result showed brown pigments deposited mainly in red pulp compared to the control group. The result presented that this nanoparticle could penetrate the membranes and reaches into many body organs because can penetrate the brain barrier, bloodstream, and many barriers to the harmful effect of acute exposure or chronic exposure to these nanoparticles.