ABSTRACT A QuEChERS-UPLC-MS/MS method was developed and validated for simultaneous determination of six pesticides (chlorpyrifos, malathion, carbofuran, thiodicarb, deltamethrin, and lambda-cyhalothrin) in dairy products. Samples (n=50), collected from a supermarket in Chongqing, China, were extracted with 1% acetic acid–acetonitrile, purified using PSA, and quantified by external-standard UPLC-MS/MS. All pesticides showed excellent linearity (0.001–0.50 mg/L, R² > 0.99), with LOQs of 0.002 mg/kg.