In a large bowl, combine the olive oil, lemon juice, garlic, oregano, parsley, salt, and black pepper.
Add the chicken cubes and toss until evenly coated.
Cover and refrigerate for at least 30 minutes, or up to 8 hours for deeper flavor.
If using wooden skewers, soak them in water for 30 minutes.
Thread the marinated chicken onto skewers, leaving a little space between each piece.
Preheat a grill or grill pan to medium-high heat.
Grill the skewers for 10–12 minutes, turning every few minutes until the chicken reaches an internal temperature of 165°F (74°C).
Remove from the grill and let the chicken rest for 5 minutes.
Serve the Greek Chicken Souvlaki Recipe with tzatziki sauce, pita bread, Greek salad, rice, or roasted vegetables.