The dataset is based on 50 soft carbonate sediment samples from the reef island Barrang Lompo in the Spermonde Archipelago, Sulawesi, SE Asia. The subsurface samples were obtained by percussion drilling at 5 coring locations on the island. From each coring location, 10 samples were retrieved in 1 m intervals, thus providing samples from a maximum depth of 10 m below surface at each site (1 m, 2 m, ..., 10 m). Laboratory data was collected between 2019 and 2021. The provided dataset contains raw grain sizes determined after dry sieving. Samples were weighed before sieving (initial mass). After sieving, fractions (diameters from 32 mm to 0.0063 mm) from each sieve were weighed to analyze grain size distribution. The collected data provides information of reef-derived sedimentation in the Holocene in the Spermonde Archipelago.