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Heavy metals pollution is one of the most important public health issues all around the world(Li et al.,2014).Heavy metals are dangerous because of their toxicity,non-biodegradability and persistence(Du et al.,2013).Chinese agricultural soils are suffering from heavy metals pollution in most of mine areas.With different fractions influencing plant uptake and affecting the food safety,an understanding of how the heavy metal different fractions distribution in paddy field soil is needed(Johnson and Hallberg,2005; Lee,2006).Soil samples were collected on paddy field in a sulfide mining area in the north region of Guangdong,China.We determined the concentration of five heavy metals(Cu,Cd,Pb,Cr,Zn)with sequentially extracted for the exchangeable and carbonate bound fraction(acid soluble fraction),iron and manganese oxide bound fraction(reducible fraction),organic bound fraction(oxidizable fraction)and residual fraction.The concentrations of heavy metals were 0.75 mg/kg for Cd,243.72 mg/kg for Cu,155.75 mg/kg for Pb,229.78 mg/kg for Cr and 229.78 mg/kg for Zn in surface soils.The concentration of Cu was 4.8 times of the Grade Ⅱ of the Soil Environmental Quality Standard of China,the acid solution fraction of Cu surpassed 68.41 mg/kg.The total concentration of heavy metals(Cu,Cd,Pb,Cr,Zn)decreased from tillage layer to bottom layer in soil profile.Although the proportion of residual fraction of heavy metals(Cu,Cd,Pb,Cr,Zn)were high in the whole of soil profile,acid soluble fraction and reducible fraction of concentration(Cu,Pb,Cr,Zn)was the highest in surface layer.In this study,the oxidizable fraction of Cu was positively correlated with four different fractions of Pb in soil profile.Acid soluble fraction of Cr was correlated with the Cu,Pb and Zn distribution,which warned that acid soluble fraction of Cd can be used to assess of degree of soil pollution in sulfide mine areas.The extraction results,the PCA analysis as well as the soil physicochemical property revealed that heavy metals distribution were controlled by the following reactive compartments: soil organic matter,clay minerals and amorphous iron oxides.The soil profile was divided three parts(0-10 cm,10-40 cm,40-80 cm)by PCA analysis.The results indicated that the heavy metals mainly came from the irrigation water in which the oxidative dissolution of mine wastes gives rise to acid,metal-enriched mine drainage,and concentration of heavy metals in tillage layer was higher than that of other layers and pose a threat to the environment and people health.