Heavy metals such as mercury (Hg), lead (Pb), cadmium (Cd), chromium (Cr), and arsenic (As), once they accumulate in living organisms, lead to heavy metal toxicity and harmful biological effects. These metals, unlike organic toxins, cannot be broken down and persist in the environment, bioaccumulating in plants, animals, and humans. One such hazardous metal that is frequently utilized in mining, metallurgy, battery, fertilizer, pesticide, and other sectors is lead (Pb). The buildup of lead in the surroundings causes unfavorable circumstances for plants, including stunted development, decreased levels of chlorophyll and cell divisions, disruptions in the absorption of nutrients, and the inhibition of enzymes. However, certain plant species sometimes survive and grow in lead-contaminated region. This tolerance possibly involves enhanced root growth and morphological adaptations, lead exclusion and sequestration, chelation and detoxification, antioxidant defense mechanisms, and phytoremediation potential. This chapter focuses on the lethal effects of lead and the mechanism of adaptive resistance in plants.