Mercury is a naturally existing element. It could be transported into human body through food chain, and harm the central nervous system. This is the first study to analyze the concentrations of mercury in different kinds of food in Taiwan. The purpose of the study was to assess the mercury intake of total diet and the health risk. Moreover, the concentration of hair mercury was used to evaluate the body burden. The mercury concentrations in foods were determined by furnace-gold amalgation mercury analyzer. Nine kinds of foods, fish, nonfish seafood, meats, soybean products, eggs, dairy products, vegetables, fruits and cereals were included in the sample. A total of 118 food composites with 574 samples were collected from three largest cities in Taiwan during 2004 to 2006. Dietary information of 446 Taiwanese was collected by using semi-quantitative food frequency questionnaire. Meanwhile, both diet information and hair sample of 355 Taiwanese that were collected. The mean mercury concentrations of nine kinds of food were significantly different (p < 0.05), ranging from 0.5 to 82.9 ng/g wet wt. The mean mercury concentrations was highest in fish, and sequentially decreased in nonfish seafood, eggs, meats, soybean products, vegetables, cereals, dairy products and fruit. All the mean mercury concentrations of foods were below the standard limits of Department of Health in Taiwan, FAO/WHO and European Commission. The dietary mercury intakes for vegetarian, general population lived in the city, fishing village, outlying islands and fishing workers were 0.16, 0.89, 1.22, 1.66 and 3.50 £gg/kg/week, respectively. There were significant differences (p < 0.05) among the five groups mentioned above. The highest mercury intake was found in the fishing workers. However, the mean mercury intakes for those five groups were still within the PTWI safe limit suggested by FAO/WHO, corresponding to 3 to 76% of PTWI. Fishes were the major source of mercury intake among nine kinds of foods for Taiwan population, corresponding to 42 to 77% of mean mercury intake. Mean concentrations of hair mercury of vegetarian, general population lived in the city, fishing village, outlying islands and fishing workers were 0.5¡Ó0.5¡B2.4¡Ó1.8¡B4.4¡Ó3.3¡B4.6¡Ó7.4 and 9.1¡Ó13.6 mg/kg respectively. Significant differences were found among the five groups (p < 0.05). The highest mercury concentration of hair was also found in the fishing workers corresponding to the result of diet intake. 2.3% of Taiwan population with hair mercury higher than the toxic level, 20 mg/kg, proposed by FAO/WHO. They were all fishing workers and outlying islanders. Multiple regression analysis revealed that the concentrations of hair mercury were significantly correlated with the frequency of fish consumption for the population lived in the city, fishing village, and fishing workers. The mercury concentrations of hair was also related with the age of people and the fish species. Aspects of nutrient balance and the health risk, consumption of small and medium-sized fish with mercury lower than 50 ng/g was recommended. No more than 150 g per week was acceptable for the people like to eat large-sized predatory fishes.