Rinse the quinoa under cold water to remove any bitterness. In a medium saucepan, combine the quinoa and water. Bring to a boil, then reduce the heat to low, cover, and simmer for about 15 minutes, or until the quinoa is fluffy and the water is absorbed. Remove from heat and let it sit covered for 5 minutes.
While the quinoa is cooking, prepare the vegetables. Chop the cucumber, halve the cherry tomatoes, finely chop the red onion, and roughly chop the parsley.
In a medium bowl, combine the cooked quinoa, cucumber, cherry tomatoes, red onion, parsley, feta cheese, and chickpeas.
In a small bowl, whisk together the olive oil, lemon juice, salt, and pepper until well combined.
Drizzle the dressing over the salad and toss gently to combine all the ingredients.
Taste and adjust seasoning with additional salt and pepper, if necessary.
Serve immediately or refrigerate for 30 minutes to let the flavors meld.