In present work, the structural, morphological, optical and photocatalytic activities of ZnS and Co2+: ZnS NPs were prepared through chemical route as hydrothermal process at room temperature. ZnS and Co2+: ZnS were characterized by using various techniques such as, XRD, SEM-EDX, TEM-SAED, UV-visible, PL and BET. The spherical-like morphology with the average crystallite size was found to be 8 to 15 nm. Among them results, it showed that the Co2+ atoms were incorporated into the ZnS lattice, forming cubic phase as the Co2+ dopant concentration increases from 0 to 2 %. The band gap energy of the ZnS and Co2+: ZnS increases from 3.5 to 4.10 eV, which enables stronger absorption of UV region. During catalytic process, Co2+ act as electron trapping center, which inhibits the recombination of the photo induced holes and electrons as showed higher degradation efficiency for MeB.