In vitro method for detecting blood plasma Amygdalin including the following steps: pretreatment of mammalian blood plasma samples including a. In Collected mammal blood plasma containing drugs of botanical compositions strengthening body resistance and dissipating blood stasis after being administered, mix well after adding 2 to 5 mol/L phosphoric acid, the volume ratio between the blood plasma and phosphoric acid being 1:2-3, applying the blood plasma to a column of Waters Oasis HLB activated by methanol and water; leaching with water and 80-100% methanol; eluting with 0.2-1% ammonia -methanol, drying and enriching the eluent under the condition of 25 to 30 °C, and redissolving the eluent with a mobile phase; detection of amygdalin with UPLC/MS method using the following measurement conditions: UPLC condition: chromatographic column: Acquity UPLC BEH C18, 2.1 x 100 mm, mobile phase A: water- Acetonitrile- Formic acid 95:5:0.1 v/v/v, mobile phase B: Acetonitrile-Formic acid 100: 0.1 v/v; MS condition: electrospray ionization ion source, detecting with positive ion mode, and mass scanning at the range of m/z 150-800, wherein the step of detecting amygdalin with UPLC/MS method detects with positive ion mode, the desolvation gas flow is 440 L/h, the desolvation gas temperature is 300 °C, the cone gas flow is 50 L/h, the ion source temperature is 100 °C, the spray capillary voltage is 3800 V, the sampling cone voltage is 30V, the extracting cone voltage is 2.00 V, the lens voltage is 0.1 V, and mass scanning at the range of m/z 150 to 800. pretreatment of mammalian blood plasma samples including a. In Collected mammal blood plasma containing drugs of botanical compositions strengthening body resistance and dissipating blood stasis after being administered, mix well after adding 2 to 5 mol/L phosphoric acid, the volume ratio between the blood plasma and phosphoric acid being 1:2-3, applying the blood plasma to a column of Waters Oasis HLB activated by methanol and water; leaching with water and 80-100% methanol; eluting with 0.2-1% ammonia -methanol, drying and enriching the eluent under the condition of 25 to 30 °C, and redissolving the eluent with a mobile phase; a. In Collected mammal blood plasma containing drugs of botanical compositions strengthening body resistance and dissipating blood stasis after being administered, mix well after adding 2 to 5 mol/L phosphoric acid, the volume ratio between the blood plasma and phosphoric acid being 1:2-3, applying the blood plasma to a column of Waters Oasis HLB activated by methanol and water; leaching with water and 80-100% methanol; eluting with 0.2-1% ammonia -methanol, drying and enriching the eluent under the condition of 25 to 30 °C, and redissolving the eluent with a mobile phase; detection of amygdalin with UPLC/MS method using the following measurement conditions: UPLC condition: chromatographic column: Acquity UPLC BEH C18, 2.1 x 100 mm, mobile phase A: water- Acetonitrile- Formic acid 95:5:0.1 v/v/v, mobile phase B: Acetonitrile-Formic acid 100: 0.1 v/v; MS condition: electrospray ionization ion source, detecting with positive ion mode, and mass scanning at the range of m/z 150-800, wherein the step of detecting amygdalin with UPLC/MS method detects with positive ion mode, the desolvation gas flow is 440 L/h, the desolvation gas temperature is 300 °C, the cone gas flow is 50 L/h, the ion source temperature is 100 °C, the spray capillary voltage is 3800 V, the sampling cone voltage is 30V, the extracting cone voltage is 2.00 V, the lens voltage is 0.1 V, and mass scanning at the range of m/z 150 to 800. UPLC condition: chromatographic column: Acquity UPLC BEH C18, 2.1 x 100 mm, mobile phase A: water- Acetonitrile- Formic acid 95:5:0.1 v/v/v, mobile phase B: Acetonitrile-Formic acid 100: 0.1 v/v; MS condition: electrospray ionization ion source, detecting with positive ion mode, and mass scanning at the range of m/z 150-800, wherein the step of detecting amygdalin with UPLC/MS method detects with positive ion mode, the desolvation gas flow is 440 L/h, the desolvation gas temperature is 300 °C, the cone gas flow is 50 L/h, the ion source temperature is 100 °C, the spray capillary voltage is 3800 V, the sampling cone voltage is 30V, the extracting cone voltage is 2.00 V, the lens voltage is 0.1 V, and mass scanning at the range of m/z 150 to 800.