This report demonstrates a facile and green fabrication method for the nickel nanoparticles using L-lysine as an efficient protecting agent. The application of green amino acid (L-lysine) enabled formation highly spherical and well-dispersed nanoparticles with average diameter in the range of 10 ±2.5 nm. UV-Vis spectroscopy was used as a primary tool to elaborately study and optimize the necessary experimental condition for the developed synthetic protocol. Fourier transform infrared spectroscopy (FTIR) was used to confirm the surface protection of Ni NPs via L-lysine molecules whereas; atomic force microscopy (AFM) and scanning electron microscopy (SEM) provided morphological and topographical view of the as-synthesized Ni NPs. In addition, small angle X-ray scattering (SAXS) and X-ray diffraction (XRD) were used to evaluate compositional characteristics of fabricated L-lysine protected Ni NPs. The as-synthesized Ni NPs demonstrated excellent catalytic potential when utilized as heterogeneous catalyst for reduction of methylene Blue (MB) in the presence of sodium borohydride (NaBH4). The observed catalytic reaction was determined to follow pseudo first order kinetics with rate constant (K) and turn over frequency (TOF) determined to be 0.0224 and TOF value of 0.00411 s-1 respectively.