Abstract： Forest felling is known to seriously affect forest-floor bryophyte population development, but few studies have done to investigate the temporal change of bryophyte population along the cutover restoration process. Selecting three preponderant forest-floor mosses distributing extensively in primary coniferous forests in the eastern Tibetan Plateau, Actinothuidium hookeri, Hylocomium splendens and Thuidium cymbifolium, we investigated their frequency, cover and biomass, as well as vascular plant cover (including herbs and shrubs) and litter, in four cutovers with similar background but with different felling time and a nearby primary spruce forest in Ramtang, Sichuan and compared their differences in population structure and biomass. We aimed to assess their changes in structure and biomass of the three moss populations following forest felling. In particular, we tried to test two hypotheses: 1) Forest-floor moss populations would decline significantly after forest felling due to environmental alteration; and 2) they would be gradually restored during the early natural restoration process of cutover vegetation. We found: 1) the three mosses all showed significant differences in cover and biomass between the cutovers and the primary spruce forest, confirming the first hypothesis; however, 2) all the three populations did not show apparent differences in population structure and biomass along the cutover restoration chronosequence, disagreeing with the second hypothesis. The large variability in cover and biomass in the cutovers, on a microhabitat scale, indicated that these three populations were more dynamic in the cutovers than in the primary spruce forest. Spearman rank correlation analysis revealed that both tree and herb covers were crucial factors impacting forest floor bryophyte population biomass. Our results suggested that the features of the three moss populations in the cutovers were indicative of their ecological adaptations and reproductive strategies and of the environmental alteration created by clear-felling, and it was difficult for recovery and restoration of two climax populations, A. hookeri and H. splendens, if only relying on natural restoration in the alpine cutovers in the eastern Tibetan Plateau. Fig 6, Tab 4, Ref44