In the present investigation, influence of rare earth Neodymium (Nd3+) on the thermal, linear and nonlinear optical properties of Potassium Pentaborate (KB5) crystal have been studied systematically. The exact weight percentage of the metal dopant was determined by Inductively Coupled Plasma analysis. Powder X-ray diffraction studies were carried out for the pure and doped crystals to confirm the structure of the grown crystals. Dielectric and photoconductivity studies were made on the grown crystals. Mechanical and thermal stability of the grown crystals were determined by Vickers microhardness and thermal studies. Nonlinear optical properties were analyzed by SHG studies.