Preheat your air fryer to 350°F (175°C).
In a large mixing bowl, combine the ground beef, breadcrumbs, Parmesan cheese, onion, garlic, egg, Italian seasoning, salt, and black pepper.
Mix everything gently until just combined. Avoid overmixing, as it can make the meatballs dense.
Using a cookie scoop or your hands, shape the mixture into approximately 2-inch meatballs.
Arrange the meatballs in a single layer inside the air fryer basket, leaving space between each one.
Cook the Air Fryer Meatballs for 10–12 minutes, flipping halfway through cooking.
Check that the internal temperature reaches 165°F (74°C).
Serve immediately with marinara sauce, pasta, mashed potatoes, rice, or your favorite vegetables.