An ultra performance liquid chromatography-tandem mass spectrometry method was developed for the separation and determination of alkaloids in papaveris content in seasonings.After the hydrochloric acid extraction and MCX purification,the samples were injected into the liquid chromatography-tandem mass spectrometry.The chromatographic separation was performed at 40℃ in the gradient elution mode using a mobile phase composed of a mixture of 0.1% acetic acid-acetonitrile and 10 mmol/L ammonium acetate at the flow of 0.2 mL/min.In this method,five kinds of alkaloids can be detected within eight minutes.The minimum detection limit of Papaverine and Narcotine were 0.8 μg/kg and 1.0 μg/kg,the minimum detection limit of Morphine,Codeine and Thebaine were 50 μg/kg.This method was simple and high sensitive and precise.It has a potential for practical applications in alkaloids determination.