Heavy metal pollution caused by industrial sewage and agricultural production is becoming an increasingly serious problem. Cadmium(Cd) is one of the most phytotoxic heavy metal elements and is attracting increasing research attention. It easily enters the food chain and poses considerable threat to human health. Vetiveria zizanioides is a tall (1-2 m), fast-growing,and perennial tussock grass that is eurytopic in terms of habitat choice. It develops a long (3-4 m), massive,and complex root system that can penetrate the deeper layers of the soil. V. zizanioides has a strong tolerance for Cd, and it can adapt to tolerate Cd at low concentrations over a long period, or high Cd concentrations over a short period.The Cd can be absorbed and stored by V. zizanioides while retaining its stability. Healthy and equal-sized plants were chosen, cleared, and cultured for 7 days in complete Hoagland nutrient solution. After the plants had grown buds, they were treated with different gradients of Hoagland's solution modified by adding Cd with cadmium sulfate (1:1) hydrate (3:8) (3CdSO₄·8H₂O) to create Cd concentrations of 0, 1, 3, 5, and 7 mg/L.The experiments were carried out separately in three different groups. The plants were harvested after 10 days. The whole plant was washed under tap water and rinsed with deionized water. The roots, stems, and leaves were separated, put into a cabinet dryer at 105℃ for 30 min, further dried in a cabinet dryer at 80℃for a another 48 h and finally milled into a fine powder (less than 200-mesh) with a stainless steel attritor. This study deals with the physiological response of the changes in chemical contents in the root, stem, and leaf of V. zizanioides seedlings stressed by excess cadmium ions (Cd²⁺) using the Fourier transform infrared spectroscopy technique (FTIR). Cadmium(Cd) accumulation in plants and its subcellular distribution (determined by atomic absorption spectroscopy) were tested under the different Cd²⁺ concentrations to elucidate the mechanism of Cd²⁺ tolerance and the accumulation characteristics of Cd²⁺ in V. zizanioides. This result indicates that after an initial decline, absorbance in roots of the dominant infrared band (near 2927 cm^-1) exhibited an increase. At low Cd²⁺ concentrations (<3 mg/L), organic acids secreted by V. zizanioides were able to chelate Cd²⁺, which leading to a decrease in carboxylic acid O-H. At high Cd²⁺ concentrations (>3 mg/L), chelating activity decreased, which was followed by an increase in organic acids. After an initial increase, absorbance changes in stems of the dominant infrared band (near 1631 cm^-1) exhibited a decline. This indicates that at low Cd²⁺ concentrations (<3 mg/L), osmosis of organic substances (e.g. amino acids, peptides, and proteins) occurred, improving Cd²⁺ tolerance.However, with the increase in Cd²⁺ concentrations, the binding force between peptide bonds and hydrogen bonds in protein secondary structure was significantly affected. In addition, the plant accumulated large amount of Cd²⁺, up to the maximum of 212.49 mg/kg (shoot) and 290.59 mg/kg dry weight (root) after 10 days when the plant was treated with a Cd²⁺ concentration of 7 mg/L. The Cd²⁺ in the shoot (stem and leaf) usually increased with increasing Cd²⁺ concentrations. Cadmium accumulated in leaves was mainly distributed in the cytoplasm, followed by the cell wall, and was least distributed in the mitochondria and chloroplast. This study demonstrates the potential of the Fourier transform infrared spectroscopy as a non-invasive and rapid technique for monitoring of plants stressed with heavy metals.