For the marinade, combine the olive oil, garlic, lemon juice, and Greek seasoning in a small bowl. Whisk together to combine.
Place the chicken and marinade in a sealable plastic bag and shake to ensure the marinade is covering chicken. Marinate in the refrigerator for at least 2 hours or overnight.
Thread chicken onto skewers and throw away the remaining marinade. Grill on an outdoor grill or grill pan for about 5 minutes on each side. Grill until thoroughly cooked to 165° Farhenheit. Serve warm!
Serve chicken souvlaki with a side of tzatziki sauce for dipping, with a delicious Greek salad, or as the meat in a gyro.