Preheat oven to 350° and line a baking sheet with parchment paper.
In a medium bowl, combine grapes and olives.
Add in olive oil, lemon juice, lemon zest, thyme leaves, salt, and pepper. Toss to combine.
Put grape and olive mixture on the prepared sheet pan and roast for 15-20 minutes in the preheated oven until grapes are slightly shriveled and olives are slightly browned.
Cool completely and serve.