There are three soil types in South China Sea Islands, namely, Phosphic Lithomorphic Isohumisols, Holisols and Entisols, which are derived from bio-clastic and strongly calcareous sediments.In comparison with their parent materials, the Phosphic Lithomorphic Isohumisols have higher contents of P, Zn, Cu, Ba, and Cd, which tend to increase gradually with time, and lower contents of Mg, Ca, Sr, B, V, Pb, and Mo, which tend to decrease gradually with time. The above-mentioned constituents in Entisols and Holisols are similar to those in their parent materials except for P and Na, whose contents are higher than those in parent materials. The factors affecting element distribution are mainly special bioclimate and parent materials, which also result in the remarkable influence of soil-forming time on element distribution. Element availabilities of Phosphic Lithmorphic Isohumisols are characterized by enrichment in P, Zn, and Cu, and those of Holisols by enrichment in B. The factors affecting element bioavailabilities in soils are soil acidity, soil organic matter, cation exchange capacity and total element content, among which total element content has the strongest effect on P, Zn, and B availabilities, resulting that distribution of their element availabilites are similar to that of their total element contents.