Peat properties from an ombrotrophic bog (Store Mosse bog) located in south-central Sweden. The data include peat bulk density analysis, peat accumulation rates (peat-AR), and an age model based on 16 radiocarbon dates, on a 678 cm long peat sequence which was collected in November 2018 (using a Russian corer) and reaches almost 10000 cal years BP in basal age. The peat sequence is based on 9 consecutive peat cores (of 1 m each) obtained from two alternating holes in the southern part of Store Mosse bog. The peat cores were subsampled into 1 cm slices and then stored in a cold room before analysis. The bulk density analysis was made at a 1 cm resolution by taking a cube of peat (roughly 1 cubic cm) from each subsampled slice to be freeze-dried, then weighed and measured (using a caliper) to calculate its density - these values were then used to align the cores to obtain one composite peat sequence with a depth of 678 cm. The age model was created using R_Bacon which utilizes the IntCa13.14C calibration curve, based on 16 radiocarbon age dates of hand-picked plant macrofossil remains. Using the bulk density data and the ages from the age model, the peat accumulation rates (peat-AR) were calculated at 1 cm resolution by dividing the total mass (g/m²) by time between each sample, presented as g/m²/a.