Whisk together oil, lemon juice, garlic, and rosemary in a large bowl. Add shrimp; gently toss to coat shrimp. Refrigerate 15 minutes.
Heat grill to medium-high.
Remove shrimp from refrigerator; skewer 3-4 per skewer. Season with salt and pepper to taste. Grill shrimp 2-3 minutes on each side. Remove from grill to serving platter.