Gold nanoparticles (AuNPs) are particles with small size from (1–100 nm),having large surface-tovolume ratio, unique physical and chemical properties, high robustness and quantitive and qualitative target-binding properties.There are many applications for (AuNPs) in pharmaceuticals using,Such as using in cancer therapy, AuNPs have a tunable optical properties that allow the absorption of light at near UV to near infrared which due to entering of cell.In Radiotherapy,AuNPs accumulates in the tumor cell and acting as a trap to focus the radiation in the tumor and limit for action in normal tumor vicinity,for Angiogenesis inhibition, AuNPs have the capabilityfor prevent phosphorylation of proteins which involved in this process of angiogenesis, by their binding to the cysteine residues in heparin-binding growth factors.AuNPs as delivery systems(DDSs) which includesspecific targeting,nanoparticles having selectivity for cancer target which achieved by the enhancement of cellular accumulation of AuNPs by an active targeting to cancer cells.AuNPs for drug/cargo delivery.Functionalizing of AuNPs with a plethora of different cargos due todrug deliverydevelopment.Stable nano - vectorization systems in the blood-stream, drug release rate and clearance of the vector are importantproperties for nanoparticles using as DDSs.AuNPs for gene therapy,when conjugated to AuNPs, siRNAs exhibit increased stability, cellular uptake and efficacy in physiological conditions, retaining the ability to act through the RNAi pathway.