Representive cured products such as ham and sausage produced in Korea were purchased at retail and cooked using heating tools such as a gas range (GR), an electric range (ER) and electric range after boiled (BE). Changes of N-nitrosamine (NA), nitrate and nitrite in the cured meats containing< $2.0;mu extrm{g}/kg$ of N-nitrosodimethylamine (NDMA) were checked and analyzed during their cooking process. Contents of nitrate and nitrite in ham products prior to cooking were 2.0 and 1.8 mg/kg, respectively; their contents in regular hams were slightly increased, but those of nitrate in press hams were decreased while those of nitrite were increased during its cooking process. Their contents in sausage products were 1.8 and 0.9 mg/kg; those of nitrate were decreased, while nitrite were slightly increased during its cooking process. NDMA detected only NA in all the collected cured products. Changes of NDMA, regardless of cooking methods, tend to drastically increase in all samples after their cooking; Its contents were increased by average 6.0~70.7 times in the GR samples, by average 2.4~39.2 times in the ER samples and by average 7.0~56.3 times in the BE samples. Virtually, the fact that all of this nitrosamine appeared to arise by the action of precursor such as NOx was produced during the cooking of cured products.