Objective To investigate and analyze the iodine nutritional status of school-age children six months after implementation of a new standard of iodized salts in northern area of Jiangsu Province,and to provide a basis for control of iodine deficiency disorders.Methods According to the water iodine content,northern area of Jiangsu Province was divided into low,moderate and high iodine areas (the water iodine contents were ＜ 10,l0-150 and ＞ 150 μg/L,respectively).Two towns were selected in each area; one elementary school was selected in each town; and 120 children aged 8-10 were selected in each school.The samples of urine,household salt,and water in each town were collected.Urinary iodine content was tested by arsenic cerium catalytic spectrophotometry;iodine content of household salt sample was determined by direct titration; iodine content of water sample was tested by cerium sulfate catalytic spectrophotometry.Results In low,moderate and high water iodine areas,240,242 and 242 urine samples of 8-10 years old children were tested; urinary iodine median was 135.49,183.62 and 448.99 μg/L,respectively,and the difference between groups was statistically significant (x2 =165.56,P ＜ 0.05).In low,moderate and high water iodine areas,100,131 and 117 household salt samples were tested,and the median of salt iodine was 21.88,22.01 and ＜ 5 mg/kg,respectively.Water samples collected in low,moderate and high iodine areas were 12,14 and 10 copies,respectively,and the median of water iodine was 8.89,38.52 and 189.25 μg/L,respectively,and the difference between groups was statistically significant (x2 =22.27,P ＜ 0.05).Conclusions The iodine nutritional condition of 8-10 years old children in low,moderate water iodine areas in northern area of Jiangsu Province is appropriate.The new standard is suitable for iodine nutritional needs in the area.The iodine nutritional condition in high water iodine area is excess,iodine intake should be reduced.