[Objective] To optimize the extraction process of total flavonoids from Melilotus officinalis.[Method] The effects of extraction solvent,extraction temperature,solid-liquid ratio,methanol concentration,extraction duration,and extraction times on the extraction rate of total flavonoids from Melilotus officinalis were investigated and the extraction process was optimized by using single-factor tests and the orthogonal test.[Result] The optimum extraction process was obtained as followed:solid-liquid ratio of 1:30 (g/ml),methanol concentration of 80%,extraction temperature of 60 ℃,extraction duration of 2 h and extraction times of 2.Under the above condition,the extraction rate of total flavonoids from Melilotus officinalis was approximately 1.42%.[Conclusion] The heat reflux method is stable,effective and suitable for industrialization,which will provide references for the development of total flavonoids from Melilotus officinalis. [Objective] To optimize the extraction process of total flavonoids from Melilotus officinalis. [Method] The effects of extraction solvent, extraction temperature, solid-liquid ratio, methanol concentration, extraction duration, and extraction times on the extraction rate of total flavonoids from Melilotus officinalis were investigated and the extraction process was optimized by using single-factor tests and the orthogonal test. [Result] The optimum extraction process was obtained as follows: solid-liquid ratio of 1:30 (g / ml) %, extraction temperature of 60 ℃, extraction duration of 2 h and extraction times of 2.Under the above condition, the extraction rate of total flavonoids from Melilotus officinalis was 1.42%. [Conclusion] The heat reflux method is stable, effective and suitable for industrialization, which will provide references for the development of total flavonoids from Melilotus officinalis.