Ni-Co/ZrO2 (NCZ) nano-structure catalysts prepared by the hydrothermal method (NCZ-hyd) and conventional impregnation (NCZ-imp) method. The comparative catalytic activity and coke resistance for each prepared catalyst were examined in steam reforming of phenol and polyethylene terephthalate (PET) plastic waste. The Physico-chemical catalysts properties were characterized by N-2-adsorption, XRD, FTIR, TEM, SEM, EDX, H-2-TPR, CO2-TPD, and TGA. The effects of preparation methods of NCZ nano-structure catalyst on the catalytic performances in PET-phenol steam reforming were investigated. The NCZ-hyd nanostructure catalyst exposed more outstanding catalytic activity and more excellent coke resistance in comparison with the NCZ-imp. The experimental findings exhibited that catalyst synthesized by hydrothermal method were uniform with the size of 8.8 nm, while NCZ particles prepared by conventional impregnation method were un-uniform, un-shaped, and agglomerated, and the size distribution of its particles was from 25 to 50 nm. PET-Phenol conversion and hydrogen yield of 56.5% and 52.5% for the NCZ-imp while 67.6% and 64.8% for the NCZ-hyd catalyst were achieved, respectively. The kinetic study of steam reforming of PET-phenol was also implemented. The activation energy was found to be 69.03 J/mol for NCZ-imp while 107.3 J/mol for the NCZ-hyd nanostructured catalysts. The PET-phenol steam reforming produced valuable liquid products such as benzene, 2-methyl phenol, and dibenzofuran which is one of the crucial keys to solving the waste plastic recycling problem. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.