Gather all ingredients. Preheat the air fryer to 390 degrees F (200 degrees C).
Rinse and dry salmon fillets with a paper towel. Mist fillets with cooking spray.
Mix together Cajun seasoning and brown sugar in a small bowl until combined; spread onto a plate.
Press fillets, flesh-side down, into seasoning mixture.
Spray the basket of the air fryer with cooking spray and place salmon fillets skin-side down. Mist salmon again lightly with cooking spray.
Close the lid and cook in the preheated air fryer for 8 minutes. Remove from the air fryer and let rest for 2 minutes before serving.
