To clarify the residue characteristics of ametryn in the growth cycle of corn， and comprehensively evaluate its long-term dietary risk to Chinese residents， an efficient and sensitive analytical method was developed for ametryn in corn， corn stover， sweet corn and sweet corn stover in the study. The samples were extracted with acetonitrile， purified by dispersive solid phase extraction (d-SPE)， and determined by gas chromatography-mass spectrometry (GC-MS). The mean recoveries and relative standard deviations were 82.0%-108.0% and 1.3%-14.4%， respectively， and the limit of quantitation was up to 0.001 mg/kg. Ametryn can be stored stably for 280 d in corn， corn stover， sweet corn and sweet corn stover at -20 ℃ under dark， and the average degradation rates were -1.3%-18.9%. The residues of ametryn in corn stover and sweet corn stover were significantly higher than those in corn and sweet corn stover (P < 0.05). The supervised trials median residue (STMRs) and the highest residues (HRs) of ametryn in four corn products were 0.003-0.066 and 0.009-0.254 mg/kg， respectively. The chronic dietary risk (ADI%) of ametryn in registered crops (corn， sugarcane and pineapple) was 0.09%-1.18%. The ADI% of ametryn in urban areas were significantly higher than that in rural areas， and the ADI% of ametryn in female were significantly higher than that in male. The children aged 2-6 years suffered the highest exposure of ametryn (ADI%， 0.83%-1.18%). Although ametryn have an acceptable dietary risk for Chinese consumers， it's necessary to continuously pay attention to the increasing risks caused by the bioaccumulation， especially for children. Meanwhile， the high potential exposure risk of ametryn from corn stover should be alerted in forage or agricultural applications.