The preparation, characterization and catalytic test of alloy type poly(N-vinyl-2-pyrrolidone)-protected nickel-ruthenium nanoparticles (3.8 +/- 1.6 nm) (Ni-Ru@PVP) to liberate hydrogen from ammonia borane via hydrolysis have been reported in the present study. Ni-Ru@PVP nanoparticles have easily been synthesized by simultaneous reduction of suitable water-soluble nickel and ruthenium salts in the mixture of water/ethanol by a modified method of alcohol reduction with PVP as both reducing agent and stabilizer. They have been characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. They have been detected to be highly efficient and durable catalysts to liberate hydrogen from ammonia borane via hydrolysis under ambient conditions. Among prepared catalysts, Ni0.5Ru0.5@PVP nanoparticles provided mean turnover frequency (TOF) of 300 min(-1)and activation energy of 46.8 +/- 1.2 kJ mol(-1)in this hydrolysis reaction.