The catalysts containing Ru, CuCo and trimetallic RuCuCo nanoparticles were successfully synthesized by in-situ reduction of Ru, Cu and Co salts into the highly porous and hydrothermally stable metal-organic framework MIL-101 via a simple liquid impregnation method, and then characterized the structure, size, composition and specific area of the catalysts with different metal nanoparticles loading by XRD, TEM, EDX, ICP-AES, XPS and BET techniques. Their catalytic activities had been examined in ammonia borane hydrolysis to generate hydrogen gas. The result shows that the as-synthesized RuCuCo@MIL-101 exhibits a higher catalytic activity than those of monometallic Ru and bimetallic CuCo counterparts loadings, owing to the strong trimetallic synergistic effects, uniform distribution of nanoparticles as well as bifunctional effects between RuCuCo nanoparticles and the host of MIL-101, with the turn over frequency (TOF) value of 241.2 mol H-2 min(-1) (mol Ru)(-1) and the activation energy (Ea) is determined to be 48 kJ/mol. Moreover, this catalyst exhibits satisfied durability after five cycles for the hydrolytic dehydrogenation of ammonia borane. (C) 2015 Elsevier Inc. All rights reserved.