Objective To investigate the matrix effects of 5 alkaloids such as papaverine and morphine in 3 different food matrices by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry. Methods The matrix effect was analyzed before and after the extraction of the blank solution spiked with different concentration of the standard solution. The matrix effect of the determination of the 5 alkaloids was evaluated by fitting the standard curve and comparing the slope and intercept. Results The matrix effect of solid and semisolid matrix were strong, and narcotine, thebaine and codeine were easily influenced by the matrix effect. The effect of matrix effect could be effectively reduced or eliminated by optimizing the gradient elution program, adding internal standard solution and dilution samples. Conclusion The matrix effect was closely related to the type of sample matrix and the structure of compound. The improved method of matrix effect in this study could provide reference for the determination of poppy husk alkaloids in different sample matrix.