Preparation of highly dispersed supported metal catalysts, which has high activity and selectivity, is still one of the main challenges for catalysis science. Highly dispersed supported metal catalysts via an economical incipient wetness impregnation method by impregnation of a small amount of oleic acid mixed with metal nitrate on catalyst support is reported herein. XRD, TEM(STEM), SEM, XPS, FTIR and EXAFS results revealed that the small amount of oleic acid and metal nitrate solutions would in-situ self-assemble to form core shell precursors (metal nitrate species as core and metal oleate as shell), and metal agglomeration during heat treatment was drastically prevented by the steric hindrance of the shell structure. Therefore, the novel and facile method was named as in-situ self-assembled core shell precursor route. The effectiveness of this method was attested by copper and nickel on silica catalysts. Compared to the conventional preparation method, the as-prepared highly dispersed metal catalysts of Cu/SiO2 and Ni/SiO2 exhibited excellent catalytic activities for water gas shift reaction and carbon dioxide reforming of methane at high temperatures. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.