Preheat the air fryer to 400°F (200°C) for 5 minutes.
In a medium bowl, toss the halved baby potatoes with olive oil, garlic powder, smoked paprika, 1/4 teaspoon salt, and 1/8 teaspoon black pepper until evenly coated.
Place the seasoned potatoes in the air fryer basket in a single layer. Cook for 12 minutes, shaking the basket halfway through to ensure even cooking.
While the potatoes cook, season the salmon fillets with the remaining 1/4 teaspoon salt and 1/8 teaspoon black pepper.
After the potatoes have cooked for 12 minutes, carefully place the salmon fillets skin-side down on top of the potatoes in the air fryer basket.
Add lemon slices on top of the salmon fillets.
Continue cooking for an additional 8 minutes, or until the salmon reaches an internal temperature of 145°F (63°C) and the potatoes are tender and crispy.
Remove the salmon and potatoes from the air fryer. Sprinkle chopped fresh parsley over the dish before serving.