Edible young leaves and seedlings are eaten raw or cooked, added to salads. Older leaves are used as a garnish or flavouring. a condiment for tofu and as a garnish for tempura.

Leaves from the purple cultivars are used to colour preserved fruits. The leaves can also be dried for later use.

The seeds are preserved in salt or are used as a spice in pickles, tempura and miso. They are one of the ingredients in 'Shichimi' or 'seven spice' mixture. The seed can also be eaten cooked.

An edible drying oil is obtained from the seed.

The plant yields an essential oil which is used as a food flavouring in candies and sauces.

The leaves, stems and seeds of shiso are often used in Oriental medicine. It is a pungent, aromatic, warming herb that is antibacterial, antidote, antipyretic, antiseptic, antispasmodic, antitussive, aromatic, carminative, diaphoretic, emollient, expectorant, pectoral, stomachic and tonic.

The leaves are used in the treatment of colds, chest stuffiness, vomiting, abdominal pain etc.

The seed is antiasthmatic, antitussive, emollient and expectorant. It is used internally in the treatment of asthma, colds and chills, nausea, abdominal pain, food poisoning and allergic reactions (especially from seafood), bronchitis and constipation.

The stems are a traditional Chinese remedy for morning sickness.

This herb should be avoided by pregnant women.