Gather all ingredients. Preheat an air fryer to 400 degrees F (200 degrees C).

Place green beans in a large bowl. Whisk together sesame oil, soy sauce, rice wine vinegar, garlic, and red pepper flakes in a separate bowl, then pour over green beans. Toss to coat and let marinate for 5 minutes.

Place 1/2 of the green beans in the air fryer basket.

Cook in the preheated air fryer, shaking basket halfway, until crispy, about 10 to 12 minutes. Repeat with remaining green beans.