Preheat the air fryer to 375°F.
Add the green beans, oil, salt, pepper, and garlic powder to a large bowl. Toss together until the beans are coated.
Spread the green beans in a single layer in the air fryer. You will probably need to cook in two batches.
Cook for 8-10 minutes, depending on how soft you like your beans.
Remove from the air fryer and garnish with grated Parmesan cheese before serving.
