The present invention provides an extract of betel nut for improving gastric motility and its preparation process and application. The preparation process includes the following steps: take fried betel nut Chinese medicinal material and crush it, and use ether, ethanol, and chloroform in a volume ratio of 1:0.2-0.3:0.03- 0.05 as the extraction solvent, then add carbonate buffer, shake for 20-40 minutes, heat and reflux for 20-40 minutes, collect the extract, repeat the reflux extraction for 2-3 times, combine the total extract, add composite adsorption agent, the composite adsorbent is made of chitosan, diatomaceous earth, and activated carbon, and left to stand for 15-20min; filtered, and the filtrate is concentrated under reduced pressure at 60-70°C to form a thick paste, dried, and obtained. The betel nut extract obtained by the present invention not only significantly improves the transfer rate of arecoline, arecoline, and areca nut polyphenols, but also effectively removes heavy metals such as lead, arsenic, and mercury, improves the activity and safety of the areca nut extract, and can significantly reduce phenols in the stomach of mice. Red residual rate, has a good gastric emptying effect, can be better used in the preparation of drugs to improve gastric motility.