Abstract: Lead pollution is a major environmental problem where leaded petrol is used. The effect of lead levels on plants (date palm Phoenix dactylifera and tomato Lycpersicon esculentum Mill.) and the proximity to major roads on lead levels have not been investigated in the Sultanate of Oman. A study is conducted to find out lead levels in an area near a major highway and the effect of high lead levels on plant growth. The results indicate that contamination by lead decreases rapidly with increasing distance from the highway. Atmospheric depositions appeared to be the main contributor to plant contamination by lead. The absolute amount of lead absorbed by plants is positively correlated with the amount of lead in the soil, whereas the percentage uptake showed a negative correlation with lead concentration in the soil. Lead concentrations of 100, 500 and 1000 ppm have significant effects on roots of tomato plants. SOS-PAGE studies revealed the presence of two new low-molecular weight proteins associated with lead stress.