CoS-1 catalyst was prepared via a hydrothermal treatment and synthesized from Ludox silica and cobalt nitrate as silicon and cobalt sources respectively. The prepared solid material was characterized using X-ray diffraction (XRD) , infrared (FT-IR) and UV-Vis spectroscopy techniques. The incorporation of divalent transition metal (Co) leads to the formation of the silicalite-1 with divalent cations on extra framework positions. A MFI structure with high crystallinity was obtained. The oxidation reaction of cyclooctene was carried out using CoS-1 as a catalyst and tert-butyl hydroperoxide (TBHP) as an oxidant.