Hydrogen (H 2 ) is a clean energy that holds great promise as a sustainable alternative to fossil fuels. H 2 storage has gained increasing research interest in recent decades. Hydrate-based H 2 storage technology in the presence of thermodynamic promoters is promising for large-scale H 2 storage due to the mild storage conditions required, the nonexplosive nature, and the easy recovery of the stored H 2 . However, sluggish H 2 hydrate formation kinetics and low H 2 storage capacity pose major challenges for large-scale applications. In this study, we aim to elucidate the tuning effect of tetrahydrofuran (THF) no more than its stoichiometric concentration (5.56 mol %) on H 2 −THF hydrate kinetics based on systematically designed kinetic experiments with morphology observation at macroscale complemented with microscale characterization of the synthesized H 2 −THF hydrates. 3.5 mol% THF yielded a superior H 2 gas uptake of 2.36 v/v compared to 5.56 mol % THF. The H 2 −THF hydrate morphology transited from slurry-like in the aqueous phase to plate-like at the gas−liquid interface with increasing THF concentration (C THF ). Single H 2 molecules were identified to be enclathrated in the 5 12 small cages of the H 2 −THF sII hydrate for all C THF based on spectroscopic analysis. THF and binary H 2 −THF hydrates were identified, and the ratio of the THF hydrate to the H 2 −THF hydrate increased with increasing C THF based on calorimetric analysis. Higher H 2 gas uptake achieved with C THF less than 5.56 mol % was closely linked to the morphology of the H 2 −THF hydrate, which in turn was controlled by C THF . The coexistence and the ratio of THF and H 2 −THF hydrates under various C THF first reported in our study suggested that optimizing C THF was key in achieving high H 2 gas uptake. These findings provide insights for understanding the tuning effect of H 2 −THF hydrates at multiscales and guide the optimization of thermodynamic promoter concentrations in future large-scale hydrate-based H 2 storage applications.