Using a plot study, this research aimed to assess the possible contamination of Tehran surface groundwater by heavy metals which lead to considerable effects on water, soil and plants. For this purpose, four experimental plots were spread with silty loamy soil collected from Varamin plain in the southern part of Tehran with an agricultural application. The plots were irrigated with four different types of regimes. In this study, two types of plants, including lettuce and spinach, were planted in four different plots and then regularly irrigated. After irrigation phases, the soil samples were taken from 0 up to 100 cm depth intervals from each plot and concentrations of four heavy metals, including cadmium, zinc, nickel and lead, were measured in each sampling by means of atomic absorption spectrophotometer. In order to find the relative concentrations of metals available to plants, three different reagents, such as deionized water, calcium chloride and diethylene triamine pentaacetic acid (DTPA), were selected and applied to the four proposed plots into three sections of the soil depths. Present metal mobility was determined by measuring the concentration of metals in the soil profile and leachate. Results showed that most accumulation of heavy metals was observed in the surface layer of the soil. However, through shrink-swell cracks heavy metals can penetrate into the subsoil layers and consequently contaminate the surface groundwater. The concentrations of metals are increased significantly in the soil and plants of plots compared with control plot. Long-term irrigation with effluent (Plot 3) and sludge (Plot 4) increased heavy metal contents in soil and plants and made this practice unsafe to be applied by man.