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Present study deals with stand structure, biomass, productivity and carbon sequestration in oak dominated forests mixed with other broad leaved tree species. The sites of studied forests were located in Nainital region between 29⁰58^’N lat. and 79⁰28’ E long at 1500-2150 m elevation. Tree density of forests ranged from 980-1100 ind.ha^-1. Of this, oak trees shared 69-97%. The basal area of trees was 31.81 to 63.93 m²ha^-1.R. arboreum and Q.floribundashared maximum basal area 16.45 and 16.32 m²ha^-1, respectively in forest site-1 and 2 whileQuercus leucotrichophorashared maximum (35.69 m²ha^-1) in site-3. The biomass and primary productivity of tree species ranged from 481-569 t ha^-1and 16.9-20.9 t ha^-1yr^-1, respectively. Of this, biomass and primary productivity of oak tree species accounted for 81 to 95 and 78 to 98%, respectively. Carbon stock and carbon sequestration ranged from 228 to 270 t ha^-1and 8.0 to 9.9 t ha^-1yr^-1, respectively. The share of oak tree species ranged from 81 to 94.7 and 79 to 97%, respectively. The diversity of tree species ranged from 0.03 to 0.16 in forest sites-1, 2 and 3. The diversity of oak species was 0.08-0.16 in all the forest sites. Thus it is concluded that among the oak tree species,Quercus floribundaandQuercus leucotrichophorawere highly dominated in the studied forests. The climax form of oak dominated trees in the studied forest sites depicted slightly lower richness and diversity of tree species compared to the forests in the region and elsewhere. As far as dry matter and carbon of forests is concerned, these estimates are close to the earlier reports of forests in the region. Therefore, studied forests have the potential to increase the diversity, productivity and carbon sequestration of forest tree species by providing the adequate scientific conservation and management inputs.