Remove salmon from fridge 10 minutes before cooking. Pat completely dry with paper towels.
Mix garlic powder, smoked paprika, salt, and pepper in a small bowl.
Drizzle olive oil over salmon fillets and rub evenly. Season the flesh side with spice mixture.
Preheat air fryer to 400°F (200°C) for 3-4 minutes.
Place salmon skin side down in the air fryer basket. Do not overcrowd.
Cook for 10-12 minutes until internal temperature reaches 145°F.
Remove carefully and let rest for 2 minutes.
Squeeze fresh lemon juice over salmon and serve immediately.