Distribution, mobility, and toxicity of nickel is of great importance especially in soil under reuse of drainage water for irrigation. South Port Said plain, about 200,000 feddans, is considered one of the national projects that depend on the reuse of the drainage water for irrigation after mixing with Nile water. To define the natural and anthropogenic origins of nickel, sequential extraction protocol has been used in this study. The obtained results indicated that the chemical speciation of nickel fractions in the soil can be arranged in the following order: F₁- soluble (So-) < F₂-exchangeable (Ex-) < F₅-bound to organic matter (OM-) < F₃- bound to carbonate (Car-) < F₄-bound to Fe-Mn oxyhydroxides (Fe-Mn-) and < F₆-residual (Res-). The total Ni concentration in the studied soils was 20.74 and 103.00 mg/kg. However, almost all the total content of nickel in soil was lower than the pollution level of nickel in soil (i.e., 300 mg/kg) and in sewage sludge (i.e., 420 mg/kg). The calculated values of geo-accumulation index (I_geo) for all samples were in class ‘0'. This means that the studied area is considered within the uncontaminated category. In addition, the contamination factor (CF) values are less than 1. So, it indicated that CF for Ni is under low degree of contamination. Moreover, the highest bioaccumulation (BAC) which is 3.04 occurred in roots of Sugar beets (beta vulgaris) at location 5 and its lowest value (1.007) occurred in the leaves of Wheat (Tritium Vulgare) at location 9.