Silver nanoparticles (SNPs) are one of the most frequently used nanomaterials because of their antimicrobial properties. It can be prepared by physicochemical and biological method. Silver ions has toxic effects on many pathogens, including bacteria, viruses, and fungi. Because of relatively low toxicity of SNPs in humans, it has been used in various medical applications. Decrease in particle size of silver nanoparticles may leads to increase in antibacterial activity which has been associated with the increasing surface area to mass ratio. As various diseases is triggered by these microorganism so pharmacological evaluation of silver nanoparticles may be fruitful in those disease which occurs due to bacteria, fungi and virus. The present review deals with various method of preparation and reported preclinical activity of silver and its derivatives.