Objective To investigate the dietary iodine intake and iodine nutrition status among adults in Han and ethnic minority areas of Guangxi, and to provide a basis for preventing iodine deficiency diseases. Methods Based on ethnic distribution and geographical location, a cross-sectional study method was used to select a total of 679 adults from 5 counties in Guangxi. A household survey was conducted using a 3-day 24-hour dietary review method to investigate dietary intake, and a weighing method to investigate consumption of edible oils and seasonings. Drinking water, salt and random urine samples were collected to detect water iodine, salt iodine and urine iodine levels, respectively. Results The median values of water iodine in Guangxi was 4.0 μg/L. The median of salt iodine was 25.3 mg/kg. The median salt iodine consumption for the Han and minority populations were 23.2 and 25.7 mg/kg, respectively. The difference was statistically significant（Z=–8.088,P=0.000）. The median urinary iodine was 183.7 μg/L. The MUI of the Han and minority populations were 199.3 and 177.5 μg/L, respectively. The difference was statistically significant（Z=–2.205,P=0.027）. The per capita salt intake was（6.4±5.0）g/d, which were（5.6±2.9）and（6.6±5.3）g/d in the Han and minority populations. The difference was statistically significant（t=–2.825, P=0.005）.The median of dietary iodine intake was 144.5 µg/d, which were 151.9 μg/d and 140.0 μg/d in the Han and minority populations. There was no significant difference between them. Food iodine intake was 25.0 µg/d, and contribution rate was 22.4%. Water iodine intake was 5.0 µg/d, and contribution rate was 5.1%. Salt iodine intake was 103.2µg/d, and contribution rate was 72.5 %. There was a significant difference in iodine intake from food and water among different ethnic groups（Z food=–15.035, P food=0.000; Z water=–6.715, P water=0.000）. Of the dietary iodine intake, 14.5% of the participants in this study were less than EAR, 20.6% between EAR and RNI, 63.6% between RNI and UL, and 1.3% higher than UL. There were statistically significant differences in the distribution of dietary iodine intake among different ethnic groups（χ²=19.888,P=0.000）. Conclusion The iodine intake and iodine nutrition of adults in Guangxi are at an appropriate level, and iodized salt remains the main dietary source of iodine in iodine deficient areas. Population iodine nutrition monitoring should be continuously conduction, and the amount of iodized salt should be adjusted at appropriate times to ensure a suitable iodine nutrition level for the entire population.