Abstract: Determination and evaluation on content of 13 kinds of nutrient component and 4 kinds of heavy metal in Hanchunred water caltrop and Jiayuwater caltrop were carried out. It indicated that,nutrient component content of Hanchunred water caltrop was higher than that of Jiayuwater caltrop in its totality;Water caltrop stem containted more content of natrium （Na）, ferrum （Fe）, manganese （Mn）, calcium （Ca）, magnesium （Mg）, dry matter, crude fiber and fewer content of protein, potassium （K）, zinc （Zn） and phosphorus （P）, comparing with 104~140 kinds of fresh vegetable. Content of selenium （Se） wasn’t check out. Content of plumbum （Pb）, arsenic （As）, cadmium （Cd） and mercury （Hg） of water caltrop stem was justified National Food Safety Standard.

Key words: water caltrop （Trapa spp.）, heavy metal, nutrient component, food safety