In a large pot, bring salted water to a boil. Add the cubed potatoes and cook until tender, about 15-20 minutes. Drain and let cool.

In a large mixing bowl, combine the cooled potatoes, cherry tomatoes, cucumber, red onion, kalamata olives, and feta cheese.

In a small bowl, whisk together the olive oil, lemon juice, oregano, salt, and black pepper until well combined.

Pour the dressing over the salad and toss gently to combine. Serve chilled or at room temperature.