The Rockets won 111-107 to secure their 50th victory of the season and become the fourth side in the Western Conference to seal a playoff berth.
Harden, who was the team's leading points scorer during the win, told reporters: "It was a great win for us, just to give ourselves confidence, especially going into the playoffs. We might see them. It was a big win for us. It shows the resilience we have."
The Rockets face the Denver Nuggets tomorrow night.