Preheat your air fryer to around 400°F.
In a small bowl, mix together the olive oil, soy sauce, lemon juice, garlic powder, black pepper, smoked paprika and salt.
Pat the tuna steaks dry with paper towels.
Brush both sides of the steaks with the marinade mixture.
Place the tuna steaks in your air fryer basket in a single layer without overcrowding.
Cook for 2 minutes on one side, then carefully flip and cook for an additional 2 minutes on the other side (adjust cooking time depending on desired doneness).
Remove from air fryer and let rest for 3 minutes.
Sprinkle sesame seeds or furikake seasoning on top before serving, if desired.
Serve and enjoy these delicious air fryer tuna steaks! 10. Try them with a side of rice and some sautéed vegetables for a complete meal.