We determined arsenic, lead, mercury and cadmium concentrations in Chinese herbal medicines sold in the United States by medical use parts. 54 kinds of herbal products including 9 medical use parts (radix, rhizoma, cortex, pericarpium, fructus, lignum, semen, folium, and herba) were analyzed using inductively coupled plasma-mass spectrometry for arsenic, lead and cadmium, and using mercury analyzer for mercury. Arsenic (median concentration, 0.25 mg/g), mercury (0.20 mg/g), lead (3.78 mg/g) and cadmium (0.39 mg/g) were detected in 71%, 54%, 35%, and 18% of 143 herbal medicine samples, respectively. A total of 27% and 12% of 143 products analyzed contained mercury and cadmium above the regulatory standards. Herba and folium (leaves of herbal plants) were the most contaminated parts from metals, whereas pericarpium, lignum and semen (outer layers and seeds) were less contaminated. This study suggests that metal contamination is different by medical use parts. Our findings provide further evidence that efforts to protect people using traditional remedies from metal intoxication should be made to enforce the regulatory standards.