In a shallow glass dish, mix the olive oil, parsley, thyme, rosemary and garlic. Place the salmon in the dish, turning to coat. Squeeze lemon juice over each fillet. Cover and marinate in the refrigerator for 30 minutes.
Lightly oil cooking grate. Transfer salmon to the barbecue and discard any remaining marinade. Cook salmon on preheated barbecue over medium heat for 8 to 10 minutes, turning once. Fish is done when it flakes easily with a fork.