Abstract:The distribution and potential ecological risk of heavy metals in the topsoil (0-20 cm) of the Yellow River Delta were investigated. The results showed that the average contents of Cu, Zn, Cr, Cd, Pb, Ni, As and Hg in the topsoil were 27.87, 79.19, 69.01, 0.383, 21.98, 33.42, 13.76 and 0.025 mg/kg, respectively, and these values were all less than the national standard value Ⅱ, except the content of Cd. The spatial distribution of above heavy metals decreased from northwest to southeast, and the highest content was found in experimental zone, while the lowest was found in core area. The evaluation of potential ecological risk index of Hakasnon showed that Cd was medium-strong ecological hazard, and the other heavy metals were minor ecological hazards, the potential risks of the different heavy metals followed the order of Cd > Hg > As > Ni > Cu > Pb > Cr > Zn. The comprehensive potential ecological risk of the protected area was minor to moderate ecological hazard, and the ecological hazard level of each functional area was experimental zone>buffer zone>core zone. Heavy metals were greatly affected by human activities, which were higher in areas close to human activities and lower in distant areas.