In a large mixing bowl, combine the diced cucumbers, halved cherry tomatoes, and finely chopped red onion.
Add the crumbled feta cheese and chopped parsley to the bowl, gently mixing to combine all the ingredients.
In a small bowl, whisk together the olive oil, red wine vinegar, dried oregano, salt, and pepper until well blended.
Pour the dressing over the salad mixture and toss gently to coat all the ingredients evenly.
Allow the salad to chill in the refrigerator for at least 30 minutes before serving to let the flavors meld.
Serve cold and enjoy!