Abstract: Enriched tungsten-186 oxide is one of the stable isotope products of tungsten. It is used to prepare the radioactive medical isotope product ¹⁸⁸WO₃, which can be used as the target material of ¹⁸⁸W/¹⁸⁸Re generator to produce medical ¹⁸⁸Re isotope product, so as to meet the increasing requirements of biomedical markers, bone cancer treatment and other medical related fields. In order to satisfy the current market demand for ¹⁸⁶WO₃, the preparation process of ¹⁸⁶WO₃ with tungsten-186 hexafluoride (186WF6) as the raw material was studied and determined. The key parameters of preparation processes were systematically optimized, and the influence of essential parameters on the ¹⁸⁶WO₃ product purity and process yield was obtained, which determined the optimal process parameters. Finally, the high conversion rate process route was achieved, and the enriched ¹⁸⁶WO₃ products were obtained. The chemical purity of ¹⁸⁶WO₃ can reach 99.91%-99.93% with the process yield of 89.8%-90.5% under the optimal process conditions. The research consequences of this article can provide a theoretical and experimental basis for the batch preparation of ¹⁸⁶WO₃, and give the technical reference for the process of preparing metal oxides from other similar gas-phase fluorides.