In order to ensure that the intake of iodine from iodized salt is adequate, the effects of cooking, storage and iedination on iodine content in iodized salt have been studied. For moni toring the analytical Performance, a qoality control exawhnation was also undertaken. The loss of iodine was greater when salt was stored in plastic bag than in glass bottle. The loss was greater in fortified salt stored at 37℃ and under 76% humidity than in that at 20 ~ 25℃ and under lower humidity. The retention of iodine varied with the kind of has and also was influenced by the water content of cooked food. In general, the retention of iodine during cooking varied considerably (from 36. 6% to 86. 1 % ). The iodine concentration in salts varied greater from 3.0 to 100.3 mg/kg in salt for markets, and from 0 to 90.0 mg/kg in salts for households. 48. 3 % of samples from markets were found to be in compliance with national standards (30 ~ 50 mg/kg), and 72.0% of samples from households were in compliance with national standartl (20 ~ 50 mg/kg). Analytical data collected from 8 of the cooperative laheratories foran analytical reference material showed a 95% codridence interval of the population mean for both precision and accuracy, falling within X± 2SD and passing quality control exdrination In order to ensure that the intake of iodine from iodized salt is adequate, the effects of cooking, storage and iedination on iodine content in iodized salt have been studied. of iodine was greater when salt was stored in plastic bag than in glass bottle. The loss was greater in fortified salt stored at 37 ° C and under 76% humidity than in that at 20-25 ° C and under lower humidity. with the kind of has and also was influenced by the water content of cooked food. In general, the retention of iodine during cooking varied considerably from 36. 6% to 86.1%. The iodine concentration in salts varied from 3.0 to 100.3 mg / kg in salt for markets, and from 0 to 90.0 mg / kg in salts for households. 48.3% of samples from the markets were found to be in compliance with national standards (30-50 mg / kg), and 72.0% of samples from households were in compl iance with national standartl (20-50 mg / kg). Analytical data collected from 8 of the cooperative laheratories foran analytical reference material showed a 95% codridence interval of the population mean for both precision and accuracy, falling within ± ± 2 SD and passing quality control exdrination