Preheat an air fryer to 380ºF.

Prepare the green beans by trimming their stems and cutting larger ones in half so they are relatively equal in size, if needed.

Place the cleaned trimmed green beans in a large bowl along with the olive oil, salt and pepper. Toss to combine.

Transfer the green beans to the air fryer and shake the basket to make sure they're in a single layer. You may need to cook in two batches. Cook until crisp tender, shaking the basket halfway through, for 8-10 minutes total.

Squeeze fresh lemon juice on top and serve immediately.