Abstract: In order to study the antioxidant and hypoglycemic activities in vitro of Perilla leaves and their extracts, the starch paste samples with Perilla leaves were prepared using a rapid viscosity analyzer, and then in vitro simulated gastrointestinal digestion was conducted. The total phenolic content before and after digestion was measured by the Folin phenol method. The antioxidant properties of the samples were analyzed by their ability to scavenge DPPH and ABTS⁺ free radicals before and after digestion. The effects of Perilla leaves and their extracts on the release of reducing sugars during the digestion of rice starch were determined by 3,5-dinitrosalicylic acid. The results showed that as the amount of active substance added increased from 5% to 15%, the area under the curve (AUC) of reducing sugar released during the digestion process showed an overall downward trend, the sample with 15% primary purified powder had the lowest AUC value (30.86 mg glucose/g). After simulated gastrointestinal digestion, the total phenol content significantly increased, the sample with 15% primary purified powder had the highest content of total polyphenol (81.04 mg GAE/100 g DW). The ability of scavenging DPPH and ABTS⁺ free radical was improved significantly (P<0.05). The sample with 10% primary purified powder had the highest scavenging ability (38.69%) of DPPH radicals, and the sample with 15% primary purified powder had the highest scavenging ability (57.25%) of ABTS⁺ radicals. It was indicated that Perilla leaves and their extracts could inhibit the glycemic reaction of rice starch in vitro and had strong antioxidant capacity.