In this study, UHPLC quadrupole-orbitrap mass spectrometry was used to collect the chromatographic information, mass charge ratio of molecular ions and mass charge ratio of secondary fragmentation fragments of 12 kinds of chloronicotinoids and their metabolites, the fragmentation pathway was analyzed, the standard database of chloronicotinoids and their metabolites were established, and characteristic fragments were screened; The independent data scanning mode was used to obtain the traceable mass spectrum information of samples, and a non targeted screening method for chloronicotinoids and their metabolites in dairy products was established. The determination limit and the detection capacity of this method were in range of 0.01 μg/kg~0.33 μg/kg and 0.03 μg/kg~0.59 μg/kg, respectively. The recoveries were 84%~104%, and the relative standard deviations were 4.4%~7.1%. The established method was applied to the screening of chloronicotinoids and their metabolites in 81 batches of pasteurized milk. It was found that the samples contained acetamiprid-metabolite-IM-1-4, which was not detected, and the content was 0.32 μg/kg. The results showed that the method was rapid and simple, and could realize the accurate qualitative and quantitative analysis of chloronicotinoids and their metabolites in dairy products.