Abstract: Tungsten (W) is widely recognized as the premier plasma-facing material (PFM) for fusion reactors. However, exposure to hydrogen (H) plasma inevitably leads to the substantial retention of H isotopes within the material, precipitating degradation issues such as blistering, swelling, and hardening. Prior studies show that material defects, such as vacancies, dislocations, and grain boundaries, can act as efficient trapping sites for H. Moreover, as a product of fusion reactions, helium (He) is heavily implanted into W via plasma irradiation. Driven by the electrophobic nature of He, these atoms aggregate at interstitial sites through a “self-trapping” mechanism, thereby forming interstitial He clusters (He_n, n indicates the number of He atoms). Although existing literature indicates that such clusters attract H, their specific impact on the kinetics of H migration and diffusion remains underexplored. In this study, the first-principles calculations were employed to investigate the dissolution of H in the vicinity of He_n in W. The climbing image nudged elastic band (CI-NEB) method was utilized to map out H migration pathways and energy barriers, while the McNabb-Foster equation was applied to quantify the influence of He_n on H diffusion. The results show that interstitial He atoms preferentially aggregate within 110 planes and form stable clusters in W. For He_n clusters with 1≤n≤7, the binding energy of H first rises and then falls with increasing He atom number, peaking at 0.77 eV (He₆). CI-NEB calculations reveal that the migration energy barrier for H around these clusters is highly dependent on the number of He atoms. For clusters containing no more than four He atoms (n≤4), the migration energy barrier from a stable site to the first-nearest-neighbor (1NN) tetrahedral interstitial site (TIS) ranges from 0.11 to 0.26 eV, which is comparable to the barrier between adjacent TISs in intrinsic W (0.18-0.23 eV). As the H atom migrates further away from the cluster, the barrier stabilizes at 0.25 eV approximately, approaching that of intrinsic W. Conversely, for larger clusters (n＞4), the migration barrier to the 1NN TIS rises to roughly 0.45 eV—approximately double that of intrinsic W. Outside this localized area, however, the migration energy barrier (0.12-0.19 eV) for outward diffusion reverts to levels similar to those in pure W. These findings suggest that, although smaller He_n clusters (n≤4) exert a negligible effect on H migration, larger clusters (n＞4) significantly impede H migration, with the hindering effect being spatially confined to the 1NN TIS. The diffusivity ratio of H is evaluated based on the McNabb-Foster model, revealing that He_n impedes H diffusion, with the hindering effect becoming more pronounced as the number of He atoms increases. Object kinetic Monte Carlo (OKMC) simulation results indicate that using the dissociation energy as the migration barrier overestimates the trapping effect of He_n on H, leading to an excessive accumulation of H in the vicinity of He_n. Therefore, a more accurate description of the kinetic processes governing H migration and diffusion around these clusters is essential for a better understanding of H distribution in W under varying He concentrations and temperatures. These findings provide theoretical insights for mitigating H retention in W materials for future fusion reactors.