La-Zr co-doped Co-B nanoparticle stabilized by Triphenylphosphine (TPP) is for the first time prepared in situ reduction by sodium borohydride at reflux condition. Obtained powders were characterized by XRD, BET, ICP, SEM-EDS and TEM techniques. TEM images depict that Co-B is appears formless and agglomerated powder. There are no agglomerated TPP stabilized La-Zr co-doped Co-B nanoparticles. It is concluded that, TPP as stabilizing agent can prevent agglomeration. TPP stabilized nanoparticle is formed as a spherical shaped particle. Particle size distribution is prepared and average size particle is about 13 nm. TPP stabilized La-Zr co-doped Co-B nanoparticle is highly active catalyst for hydrogen generation through the hydrolysis of sodium borohydride. It is also includes the full experimental details for the collection of a wealth of kinetic data to determine the activation energy (Ea = 45 kJ mol(-1). Catalytic hydrolysis of NaBH4 is first order with respect to the catalyst concentration and also first order to the NaBH4 concentration in the case of TPP stabilized La-Zr co-doped Co-B nanoparticles. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.