Add 1 1/2 cups pearl barley, 3 cups water, 1 tbsp salt, and 1 tbsp olive oil to the Instant Pot. Stir to combine.
Pressure cook the pearl barley on High for 18 Minutes.
Once the cooking time is over, allow the Instant Pot to naturally release for 10 Minutes on the Keep Warm setting. After 10 Minutes, flip the valve to release any residual steam.
Fluff the pearl barley with a fork. Serve as a side, or use as a base for grain-based salads.