Cook the orzo pasta according to package instructions until al dente. Drain and rinse under cold water.
Prepare the vegetables: dice the bell peppers, cucumber, and onion; halve the cherry tomatoes.
In a large bowl, combine the cooked and cooled orzo with the diced vegetables.
Add the crumbled feta cheese and chopped parsley to the bowl.
In a small bowl, whisk together the olive oil, red wine vinegar, salt, and pepper.
Pour the dressing over the orzo and vegetable mixture.
Toss everything gently until well combined.
Taste and adjust seasoning if necessary.
Allow the salad to sit for at least 10 minutes to let the flavors meld.
Serve chilled or at room temperature.