A method for the determination of migration levels of 7 N-nitrosamines and N-nitrosatable substances was developed using Sep-Pak AC2 connected to Dry cartridges and gas chromatography-tandem mass spectrometry.Its analytical tolerances for N-nitrosamines and N-nitrosatable substances in balloon were 1.25 μg/kg and 5.00 μg/kg,respectively.The average recoveries of 7 N-nitrosamines at a spiked concentration of 2.5 μg/kg ranged from 85% to 103% with RSDs（n=3） not more than 4.6%.N-nitrosodimethylamine（NDMA） and N-nitrosodiethylamine（NDEA） and their precursors were the most frequently nitrosamines and nitrosatable substances found in balloon samples,while N-nitrosomorpholine（NMOR）,N-nitrosopiperidine（NPIP） and N-nitrosodipropylamine（NDPA） and their precursors were not found in all balloon samples.The total migration values for 7 N-nitrosamines and N-nitrosatable substances in balloon samples were in the range of 0.036-0.964 mg/kg and 0.259-8.436 mg/kg,respectively.The risk exposure level of NDMA via oral intake from each balloon to children aged from 6 months to 4 years was grouped in the class of 0.010 mg/kg to 0.030 mg/kg body weight,which would bring high carcinogenic risk to children potentially.