Abstract: The paper deals with the effect of bioclimatic zone on the morphology and availability of manganese in soils of China by using a sequential extraction method. The distribution of manganese in soil fractions varies with bioclimatic zone. The ratios of exchangeable Mn, amorphous iron oxides bound Mn and crystalline iron oxides bound Mn to total Mn in soils in China decrease slowly, however the ratio of Mn oxides to total Mn increases from tropical zone, subtropical zone to warm-temperate zone, temperate zone. the rate of organical bound Mn to total Mn shows another model, i. e. increase from tropical zone to subtropical zone and then decrease from subtropical zone to warm-temperate zone and temperate zone. The variation of available Mn in soils is the same as that of exchangeable Mn. The available Mn in acid soils in South China comes from ex-changeable Mn and organical bound Mn and mainly from Mn oxides and exchangeable Mn in alkaline soils of North Chian.