Fill a large pot with water and bring to a boil. Place the crab legs in a steamer basket and set over the boiling water. Cover and steam for 5-7 minutes until heated through.
In a small saucepan, melt the butter over medium heat. Add the minced garlic and cook for 1-2 minutes until fragrant.
Stir in the lemon juice, salt, and black pepper. Remove from heat and whisk to combine.
Serve the crab legs with the garlic butter sauce drizzled over the top. Garnish with chopped parsley.