The McLaren driver finished ahead of Red Bull's Sebastian Vettel following a sustained attack on the championship leader at the Circuit of the Americas in Texas.
"I'm so happy. The fans were amazing, thank you," said Hamilton. "It was such a warm welcome and one of the best, if not the best, race of the year - especially for me and the team. It's been a long time since we had a win. I'm so proud of the team and grateful for the support we've had."