SummaryChemical profiles of aqueous or ethanolic extracts of 140, 170 and 200 °C‐heated perilla meal were identified by GC‐MS, and antioxidant properties of the extracts were observed via in vitro assays and in bulk oil or oil‐in‐water (O/W) emulsion. A total of 22 and 27 chemicals were found in aqueous and ethanolic extracts from non‐heated samples, respectively. As the heating temperature increased to 200 °C, the carbohydrate and derivative contents decreased significantly (P < 0.05), whereas rosmarinic acid concentration decreased in both extracts. Ethanolic extracts possessed higher antioxidant activities than aqueous extracts based on the results of radical scavenging and ferric‐reducing antioxidant power assays and the Rancimat assay, but there were no significant differences among samples (P > 0.05). In the case of O/W emulsions, aqueous extracts inhibited lipid oxidation more efficiently than ethanolic extracts at 50 °C. In particular, heat treatment decreased the antioxidant activities of ethanolic extracts and not aqueous extracts in the O/W emulsion system. Aqueous extracts are recommended in moisture‐rich emulsion‐based foods while ethanolic extracts are more suitable in a lipid‐rich environment for enhancing oxidative stability.