Solid Lipid Nanoparticles(SLNs) is a newest booming field in in the nanotechnology as it has a number of applications in the drug delivery as well as research. As they possess an ultimate size related property, these solid lipid nanoparticles have a potential to play a major role in the development of new therapeutics. Solid lipid nanoparticles due to their various advancements, holds a great significance and are preferred over other primitive carrier systems such as emulsions, liposomes, etc. Solid lipid nanoparticles can also be used for the purposes such as site-specific drug delivery as well as controlled drug delivery. This work deals with a brief review of solid lipid nanoparticles(SLNs) and their preparation procedures such as High-Pressure Homogenisation; Ultrasonication; Supercritical fluid Technique; Solvent Evaporation method; Microemulsion based method; Spray Drying method; Precipitation method; Film Ultrasound dispersion. Some Advantages,Disadvantages, Routes of Administration and Applications. The major part of interest of this review is the compilation of year wise reports done by different authors and are categorized according to various routes of administration.