The research adopts the supercritical carbon dioxide extraction as a tobacco leaf middle peasants maleic hydrazide residue before processing, high performance liquid chromatography (HPLC) as the analysis of detection means.Through single factor and orthogonal experiment, the effects of different entrainers, extraction pressure, extraction temperature, extraction time and carbon dioxide flow were determined as: the entrainer was methanol and isopropanol with methanol: isopropanol = 1: 1 (V: V), the extraction pressure was 20MPa, temperature was 55 ℃, time was 100min, the carbon dioxide flow was 23g/min. High performance liquid chromatography (HPLC) testing conditions, analysis of the adjustment better reproducibility and stability The results showed that the recovery of this method was 94.08%～97.86%, RSD were less than 6%, maleic爃ydrazide燿etection爈imit爓as 2.7μg/g.