In Xuan Son National Park, Hopea mollissima was distributed in the sub-areas 277 and 283. The tree regeneration composition was diverse, ranged from 25 to 40 tree species, and H.mollissima was dominant with the composition index of from 1.16 to 5.55. Regeneration density of the forest was high, ranged from 12,480 stems/ha to 18,800 stems/ha. The advanced regeneration of H.mollissima accounted for from 0.68 percent to 16.17 percent of overall regeneration density, and it was the dominant species in the advanced regeneration layer with the composition index of from 0.43 to 5.53. Most of regenerating trees had a good quality ( 70 percent) and were originated from seed ( 90 percent). The regeneration density of H.mollissima between under and beyond mother tree's canopy was not significantly different, while its advanced regeneration density was significant. The study results suggest that H.mollissima regenerates well in the park, and a strict protection of the species' distribution areas is necessary for conservation of this species.