In the current paper, we have studied the impact of microwave (2.45 GHz) plasma treatment of submicronic (250–600 nm) tungsten dust, upon tritium gas retention. Herein, the conducted experiments have emphasized the role of dust treatments in pure hydrogen gas versus hydrogen plasma, before the tritiation process at different pressures. The obtained tritiated dust was analyzed via room temperature desorption and dissolutions. Additionally, Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy analyses were performed to observe the changes induced by the plasma discharge. The results have shown that the Specific Surface Area of dust is enhanced by using microwave hydrogen plasma treatments, resulting in a high tritium gas retention inside the submicronic tungsten dust.