Abstract: Galli Gigerii Endothelium Corneum (GGEC) is a commonly used traditional Chinese medicine for digestion. Its odor is unpleasant, which decreases children's compliance with taking this traditional medicine. Traditional processing methods utilize heat processing methods such as stir-frying and vinegar processing to deodorize the medicine, but this affects the activity of digestive enzymes, so there is a need to find a new method for removing the fishy odor while retaining the beneficial effect of GGEC. Here we have developed the use of supercritical CO₂ low-temperature fluid extraction to eliminate the odor while retaining the medicinal benefits. Headspace-solid-phase microextraction-gas chromatography-triple quadrupole mass spectrometry (HS-SPME/GC-QQQ-MS/MS) combined with the gas activity value method was used to determine compositional differences in the product before and after supercritical CO₂ extraction and separation. Then, based on the sensory evaluation of volunteers, combined with the analysis of volatile components, the fishy odor intensity and the types of fishy odorants were compared between the raw product, stir-fried product, vinegar product and the supercritical CO₂ extract. Pepsin and amylase activity were used to compare the differences in the digestive enzyme activities with the four forms of GGEC, and Fourier transform infrared spectroscopy (FT-IR) was used to compare the differences in the structure. We compared the content of total amino acids, digestive amino acids and bitter amino acids, and an animal model of delayed gastric emptying in mice with soybean oil, based on a phenol red indicator, was used to determine differences in the efficacy of gastric emptying in vivo. The results show that the fishy odor of GGEC powder is significantly reduced after supercritical extraction, and the substances that contribute the fishy odor are only 12.8% of the raw material. The results of FT-IR analysis show that the supercritical extract of GGEC is not changed in its material structure compared with the raw product. The digestive enzyme activity titers showed that amylase and pepsin activity in the raw products are about 3.9 and 1.4 times higher than those of stir-fried products and vinegar products. The activity titers of amylase and pepsin in the supercritical CO₂extracts are about 2.7 and 1.3 times higher than those of stir-fried products and vinegar products, and there was no significant difference in the content of digestive-promoting amino acids in the four types of GGEC. The in vivo validation experiment showed that the average gastric emptying rates of the mice in the raw product group, the supercritical extract group, the stir-fried product group, and the vinegar product group were 69%, 59%, 40% and 51%, respectively. Compared with the stir-frying method and the vinegar-simmering method, the supercritical CO₂ fluid extraction method retained the gastric emptying effect of GGEC. In general, the supercritical CO₂ fluid low-temperature extraction method removes the fishy odor of GGEC as compared with the traditional stir-frying method and vinegar method, and retains the biologically active components and the effect on digestion of GGEC.