Abstract: Pesticide metabolites are important components of pesticide residues, and serve as key basis for the risk assessment of pesticides and establishment of the maximum residue limits (MRLs). The metabolic processes of pesticides in crops are complex and diverse. The formation, distribution, and characteristics of the metabolites not only affect the scientific determination of the definition of residue, but also present higher demands and challenges for the development of analytical methods. In this paper, the metabolic patterns and mechanisms of pesticides in crops were outlined, the generation pathways and characteristics of metabolites were analyzed, and the developments in analytical techniques for metabolite residue detection were summarized. It provides a reference for studying pesticide metabolism mechanisms in crops and the scientific monitoring of pesticide residues.