The invention discloses an analysis method applied to measuring residual quantity of sulfonylurea herbicide in plants. The method comprises the first step of preparing a stock solution, the second step of preparing extraction head through a QuEChERS method, the third step of processing samples and the fourth step of setting detection conditions of UPLC-MS/MS and conducting sample introduction. The method has the advantages that pretreatment is conducted through an extraction device, the sample purifying process is simple and quick, samples can be obtained through simple absorbing-pushing, results are accurate, and detection is quick; secondly, a sieve in the extraction head allows dispersion extraction, adsorbent, salt and other particulate matter can be removed out of the solution, the number of impurities is reduced, and convenience is brought to accurate quantitation; quantitation is accurate, sensitivity is high, operation is easy and quick, the consumption of the solvent is small, and the requirement for pesticide residue analysis can be met; the improved QuEChERS-method device is used for measuring the residue quantity of 10 kinds of sulfonylurea herbicide in plants.